Metal 3D Printing: An emerging opportunity

If you follow the “money” in the world of 3D Printing, it becomes clear that we are experiencing an era in which investors are betting more on metal based systems than on any other material class. However, it goes without saying that in the global materials market, polymers (thermoplastics and photopolymers) still account for more than two-thirds of the material sales in the field of 3D printing; a market estimated to reach $3 billion by 2018. The pertinent question is, “what is driving the recent surge for metals?”. It might be that metals are indeed the class of material which drives investment in engineering systems such as those found in the aircraft, oil & gas, aerospace and automotive sectors. It might also be that the interest stems from the fact that metallic parts are almost inherently deployable as functional parts rather than as samples for prototyping. Whatever the driving force might be in favour of metal, fact is that 3D printing of metals is a very expensive process. The metallic powders needed for 3D processing are expensive, the material handling raises obnoxious health-safety-environmental issues, laser processing is a high energy demanding process and the process waste material can account for up to 80% of the feedstock.

 

A possible substitute for powder based technologies is the fused filament fabrication (FFF). One of the key advantages of the FFF 3D printing technology is the ability to consume only the amount of material needed for the part being fabricated/built-up. Also, the materials (typically thermoplastic polymers) used for FFF 3D printing are generally less expensive than those used for any of the other types of 3D printing technologies. Thermoplastics can be composited with a range of other materials by simply filling them in a compounding process. Metals, ceramics, wood, carbon, glass as well as other non-meltable polymers have been used to form polymer matrix composites materials.

Metal polymer matrix material systems can now be processed by injection moulding methods requiring that the granular feedstock is first moulded into parts (so-called green body) then further processed in other to realize the full bulk strength of the metallic phase. The post processing typically involves a de-binding process (catalytic or purely thermal in order to separate the polymer binder phase from the metallic phase) and then a thermal sintering process in which the resultant brown-body is thermally densified to a pore-free solid part.

This processing approach, technically called “metal injection moulding” (MIM), is an established manufacturing process. It combines the benefits of mass production and rapid manufacturing typical of injection moulding with the inherent process safety when compared to metal casting or forging.

 

To take these processing advantages further, by using FFF 3D technology so as to manufacture parts which have relatively complex geometries at lower cost, Apium Additive Technologies GmbH has been testing the newly developed Ultrafuse 316LX filament material by BASF. This material consists of a polymeric binder phase with about 80 wt.-% stainless steel 316L particles. The FFF 3D printed green bodies were post processed using first a catalytic acid phase de-binding process followed by sintering in oven.

 

Here are some of the things we have learnt from processing this 316LX material:

It can easily be processed using Apium’s FFF 3D printing technology

-  The green-body printed from Apium’s printer have structural properties which

   enhance their survival chances when put through de-binding and sintering processes

The sintered parts meet geometric requirements

The mechanical properties of the sintered parts compare quite well with that of bulk

    316L stainless steel

The porosity of the sintered parts is generally below 2%

 

The ability to fabricate metallic parts using Apium’s FFF 3D printing technology has far reaching effects in the economics of manufacturing. It offers small and medium scale enterprise the chance to prototype or manufacture functional parts in small series at highly competitive costs.  Apium is working on a system which integrates the de-binding and sintering within its FFF 3D printing solution.

Figure 1: Ultrafuse 316LX tensile test bars green-body and sintered

Figure 1: Ultrafuse 316LX tensile test bars green-body and sintered

Figure 2: Ultrafuse 316LX sintered gear wheels

Figure 2: Ultrafuse 316LX sintered gear wheels

Contact:
Prof. Dr. Brando Okolo brando.okolo@apiumtec.com
Philipp Renner philipp.renner@apiumtec.com

High-performance Polymers for 3D printing

A broad range of materials are today capable of being processed under different kinds of manufacturing scenarios. Polymers are especially interesting in this regard because they can be conveniently processed using most existing manufacturing methods. Polymers are also able to exhibit different kinds of properties either in their pure/neat state or when filled as composites with other kinds of materials which display properties impossible in pure polymers.

High performance thermoplastics are of particular interest for applications in industrial manufacturing. This interest stems from the unique properties which this class of polymers show under extreme operating environments. Their resistance against wear loading, stability at relatively high temperatures, inertness under chemical attack and high specific strength make them key alternatives to applications where metals have traditionally been used. Therefore in the high-end engineering sectors covering health/medical, aerospace, automotive and oil&gas, high-performance polymeric materials have a role to play. An obvious performance argument is in the vehicle (space and terrestrial) development sector where weight and energy consumption are coupled, where with the ability to develop low/light weight systems generally is being considered as a key solution towards achieving energy (fuel) economy in engineering systems.  A polymeric material like PEEK (poly ether ether keton) has demonstrated to be highly competitive with engineering metallic materials like titanium, steel and aluminium alloys as a result of its bio-inertness, chemical resistance, specific strength and wear resistance. For instance, in thermo-mechanically loaded gear systems, PEEK gears work with significantly less lubricant, compared to metal gears. This advantage gives rise to longer intervals between gear maintenance and cost reduction, owing to a less frequent replacement of the gear parts.

Figure 1: Lightweight angle made from PEEK, fabricated using an Apium P 155 FFF 3D printer

Figure 1: Lightweight angle made from PEEK, fabricated using an Apium P 155 FFF 3D printer

In recent times, there have been successful efforts to process these kinds of polymers using new manufacturing methods such as 3D printing/additive manufacturing. While premium grade materials costs remain rather high especially for metals and ceramic based composites for additive manufacturing, a general interest remains high for thermoplastics. In the fields of prototyping, testing of proof-of-principle and design&production the adoption of 3D printing has been seen to change (i) efficiency, (ii) cost reduction, (iii) timeliness and (iv) job-quality, in a profoundly positive manner. The fused filament fabrication (FFF) 3D printing technology has greatly played a historic role in this regard. Driving the concept of 3D printing towards main stream manufacturing has indeed been made possible by the legacy of the FFF technology and polymeric materials, ushering the tremendous research and development work done on laser based systems, Polyjet systems, metals and ceramics. The economic sense backing an additive manufacturing business is clearly for small series production and projects requiring mass customization. Materials savings benefits of the FFF technology, the surface precisions possible in the strereolithography as well as the Polyjet systems and the speeds possible in the laser and the CLIP systems generally bring attention to AM methods. Recent studies [1] indicate that in the services sector of AM, the highest priority for service providers is in offering customized products and limited series functional products to end-users. For comparison on cost, the light weight PEEK honeycomb structure shown in Figure 1 weighs about 16 g and took about 6 hours to fabricate using an FFF 3D print at a 100% infill. The material cost for this part (10 x 45 x 115 mm3) is at 12.90€ in contrast to 15.30€ when CNC milled from a PEEK block. Clearly with the inclusion of the processing cost, machine degradation (tool wear etc) cost, cooling agents and labour cost, the CNC option would be more expensive; at least for one piece of the part.

The message for our readers is simple:

-       3D printing is a profoundly manufacturing-enabling tool
-       use this tool if you are considering small production runs or mass customization or considering having a highly agile mobile manufacturing platform
-       it is now possible to process high temperature polymeric materials (like PEEK, Ultem, PVDF, POM-c) using FFF 3D printing; the most adopted technology in the field of additive manufacturing.
 

Reference

[1] https://www.forbes.com/sites/louiscolumbus/2017/05/23/the-state-of-3d-printing-2017/print/

 

Contact:
Philipp Renner philipp.renner@apiumtec.com

Statements on resolution, accuracy and reproducibility in 3D printing

One of the persistent questions asked by potential buyers of 3D printers is about the “resolution” of the 3D printer. When prodded it becomes clear that what is actually meant to be asked is about the dimensional “accuracy” and “reproducibility” of parts printed/fabricated from the 3D printer.

Resolution in 3D printers

In the field of 3D printing, resolution (instrumental) refers to the least possible print-head displacement that can be produced within a 3-dimenional volume (often defined after a Cartesian coordinate system in x, y, z) in the build-envelop of the printer. This displacement is physically defined by the drive motors of the 3D printer. It follows then that the amount of force (rotational or linear) needed to produce an instrumentally perceivable displacement by the print-head also contributes to defining the resolution of the 3D printer. Therefore an ability of the print-head to precisely travel from one location to another within the build-envelop is what characterises the resolution of the printer. Whilst this attribute is without a doubt of great importance for fabricated part dimensional accuracy and reproducibility, it is not the sole definitive entity for part dimensional precision.

Part dimensional accuracy and reproducibility

 The dimensional accuracy of the 3D printed part is the outcome of a convolution of the 3D printer resolution, on the one-hand, and the functional tool edge radius (nozzle diameter or beam spot size) together with the rheology of the material being processed, on the other hand. An ability of the entire 3D printer system to deliver on this dimensional accuracy (even when erroneous in absolute terms) in a repeated fashion is the reproducibility. When the part dimensional accuracy is compared to the design based dimensional specification for the 3D printed part then the relative tolerance for the fabricated part can be defined.

Conclusion

Clearly a 3D printer machine exhibiting a high spatial resolution does not necessarily fabricate printed parts which have either high dimensional accuracies or high print quality reproducibility. Most 3D printers have motors which can exhibit an instrumental resolution of about 1 µm – 5 µm however the finest structural detail which can be created on fabricated parts by such machines are at least 2 orders of a magnitude (102) higher than the instrumental resolution. For the 3D printing of high temperature thermoplastic polymers in which the solid state material is thermally brought to a flow regime then solidified through a thermal gradient, the interplay between cooling rate and material flow behaviour needs to be fully moderated in order to create parts which have appreciably high dimensional accuracies.

At Apium, issues of instrumental resolution, dimensional accuracy and reproducibility are well understood. For further information about Apium`s 3D printers, please contact us.

Contact:
Philipp Renner philipp.renner@apiumtec.com

Game Changer in FFF 3D Printing: Apiums P series 3D Printers

The adoption of FFF 3D printing technologies in industrial applications is at an onset with the introduction of high performance polymers in this manufacturing space. With the launch of the first ever available PEEK filament in March 2015 by Apium (former Indmatec), a whole new area of opportunity in FFF 3D printing technology was initiated. Apium’s innovative work on 3D printer development lead to its launch of “HPP 155”, the first ever FFF 3D printer specially designed for printing PEEK in November 2015. This rather disruptive feat has ushered in perspectives never thought possible in mainstream manufacturing.

In November 2016, Apium, as leaders in FFF 3D printing of PEEK, kept its promise by announcing the development of the Apium P series 3D printers; Apium P155 and Apium P220, specially designed for multi material usage which allows users to process a wide range of polymers especially PEEK, PVDF, POM-C and PEI 9085.

One of the best features of Apium P series 3D printers is their limitless capability in processing high performance polymers. Apium`s state-of-the-art print head technology together with Apium Controlling Software with 65 adjustable parameters enables the users to control the stiffness, density, crystallinity and many other material properties in a straight forward way.

The first generation of Apium P series 3D printers; Apium P 155, is equipped with a full metal hot end with heating up to 520°C and print bed with heating up to 160°C. Apium combines the outstanding properties of high performance polymers with German engineering to bring the ability to manufacture complex structures such as honeycomb geometries and closed hollows structures with considerable material and weight savings at reduced production steps by realizing sub-assemblies in a single part.

 

A science driven observation of an unwelcome feature in 3D printed polymers

An obnoxious aspect of polymer processing is the formation of black-specks in the processed material. The black-specks have origin in the thermo-mechanical treatment of the material. It is rarely observed in the virgin resin because the synthesis which makes resin production possible is often meticulously controlled.

In the field of fused filament fabrication (FFF) 3D printing technology, black-specks can potentially develop in printed parts or at the regions of the printer where the melt exists; such as the nozzle as well as areas around the nozzle. Should this occur, it can be attributed to poor thermal management during the printing process. While the material science governing the formation of the black-specks suggests uncontrollable thermodynamically driven changes (gradients in concentration, pressure or temperature) within the melt as a prerequisite, it goes without saying that temperature plays a cardinal role.

The possible sources of the black-specks in FFF 3D printed polymers are:
- Degradation of the molten filament at the joint of the heat-break and nozzle
- Degradation of the melted filament inside the nozzle shaft
- Poorly designed nozzle tip-area such that the melt collects at the exposed surface and then degrades
- Irregular thermal loading of the melt by the heating elements
- Melt degradation due to presence of foreign particles interfacing with the melt
- Prolonged residency of a melt-batch in the nozzle shaft/barrel (HotEnd)
- Too high processing temperature

For high temperature polymeric materials such as PEEK, a tight reign on temperature based activities in the printer is desirable. Apium’s 3D printers are especially designed to ensure that black-specks do not develop in the printed parts; even for processing temperatures significantly above the melting temperature of PEEK. On the confidence of this technical achievement Apium is able to process the natural coloured (beige) PEEK for displays, demonstrations and end-user applications. These specks when present in black coloured PEEK are of course not visible or when in richly amourphous PEEK (poorly crystallized PEEK, deep brown coloured) they are hardly visible to human eyes (Figure A).

Figure A. Image of PEEK parts indicating black-specks.

Figure A. Image of PEEK parts indicating black-specks.

A Fourier Transform Infrared Spectroscopy (FTIR) analysis allows for the determination of the nature of chemical bonds in materials based on the characteristic absorption or transmittance of infrared light by the material at a relatively wide spectral range. FTIR examination of FFF 3D printed black-speck–rich and black-speck-free PEEK samples revealed (spectra in Figure B) that the aromatic group as well as the carboxyl group characteristic of PEEK structure was detected in the speck-free PEEK (filament and 3D Printed samples) while in the 3D printed speck-rich PEEK material these groups were not detected. This result supports incidence of thermal oxidation (burning) of the material with associated atmospheric CO2 observed; representing a change in which the chemistry of PEEK structure is altered (by oxidation) thus depriving the material of the properties which make PEEK unique. It follows then that the black-speck is a burnt mass of contaminant in polymers.

Figure B. FTIR spectra of PEEK samples in speck-free and speck-rich condition

Figure B. FTIR spectra of PEEK samples in speck-free and speck-rich condition

The craftsmanship needed to 3D print high quality PEEK parts using the FFF technology has been developed and consolidated at Apium. This achievement allows for the processing of other high temperature polymers using the FFF 3D printing technology without degradation of the material and the formation of blackspecks.

Acknowledgements
The FTIR analysis was performed by the ARC Centre in ADDITIVE BIOMANUFACTURING which is directed by Professor Dietmar W. Hutmacher at the Queensland University of Technology - Australia.

3D printing for medical applications

The advent of additive manufacturing technologies such as 3D printing has ushered an entirely new thinking about the efficacy of industrial manufacturing especially in areas where complexities in design prove to be challenging.

3D Printing consists of a diversity of technologies making it possible to uniquely appeal to life-critical aspects of human development such as medical practice. Some surgical tools, prosthesis and implants are in ideal cases patient-specific thus 3D printing is an economically appropriate manufacturing method for these medical devices.

Craniofacial surgery takes a prominent place in this context. Individual implants take a decisive role in those fields. In dental applications, custom-made tooth replacements are one of the possibilities given by 3D printing technologies.  The choice of the materials to be used for the implants is crucial and comes hand in hand with the technology that should be selected.

High-performance filament PEEK

High-performance filament PEEK

One of the materials that is known for its use for implants and in dental technology, is the high-performance polymer poly ether ether ketone (PEEK).  A polymer that qualifies as a material for medical applications due to its chemical stability, biocompatibility and tolerance towards radiation, as well as through outstanding wear resistance because of its mechanical properties, PEEK has a tear resistance of 98 MPa.  In addition comes a very low specific weight of 1,30 g/cm³. In dental context, PEEK benefits from low plaque attachment, a desired property for materials for tooth replacement. 

A 3D printing technology, which meets the requirements of individual parts and processes the high-performance polymer PEEK with zero material waste, can be found with the Fused Filament Fabrication (FFF). During manufacturing the material as a filament, a kind of polymer strand, will be melted through the printhead by up to 520 °C and laid down in different layers to build up the part. Controlling the solidification process of the semi crystalline polymer is crucial for a good product quality. A printer that meets the prerequisites is the Apium P 155, developed by Apium Additive Technologies GmbH. Till now the printer is only designed for industrial applications.  

 

 

Cooperation with Charité – Universitätsmedizin Berlin and Evonik Industries AG to make medical 3D printing possible

Apium P155 - High-performance polymer 3D printer

Apium P155 - High-performance polymer 3D printer

Apium Additive Technologies GmbH has started a cooperation with the Center for Dental and Craniofacial Sciences of Charité Berlin, directed by Prof. (UH) Dr. W.-D. Müller. Goal of this cooperation is a study to determine the printing performance with PEEK compounds in dental applications. The high-performance polymer 3D printer Apium P 155 with its Fused Filament Fabrication technology delivers the hardware for this 3D printing study. In a first step the 3D printer is used to fabricate different structures to test their tensile strength in comparison to extruded samples. In the next step, after satisfying results are achieved, single crown frameworks will be manufactured and compared regarding their quality. Crucial properties are the dimension precision and liability. The scale is set by CAD CAM milled structures. The Center for Dental and Craniofacial Sciences will receive assistance by Apium’s 3D printing engineers at the beginning to understand the 3D printing technology and run first sample prints. The outcome of this is the first step to develop a 3D printer for dental applications.

Besides this cooperation, Apium Additive Technologies GmbH intentions are to develop filaments for medical applications as implant material. For this, Apium cooperates with Evonik Industries AG. With testing the possibilities of Evonik‘s high-performance polymer  VESTAKEEP® PEEK – a biomaterial for medical applications – the goal is to find out how this material can be processed with FFF technology to be used as a material for 3D printed implants. The different VESTAKEEP® classes will be examined and possibly modified to achieve the desired results.

With both cooperation, Apium Additive Technologies GmbH is on the way to become the leader for FFF based medical 3D printing and will revolutionize the way of manufacturing accurate and individual implants.

Saving Potential through Lean Supply Chain Management

Apium Additive Technologies has taken a decisive step to make industrial 3D printing with high-performance polymers, like PEEK, even more cost-effective

Utilising FFF 3D printing technology, Apium is already able to provide a cost-effective means of fabricating PEEK, a high-performance polymer suitable for a variety of demanding environments.

The FFF process, a technique that transforms materials from filament into the desired geometry by rapidly depositing layer upon layer of melted material, is inherently an efficient and inexpensive manufacturing method, due to the fact that almost 100% of the processed material makes the final part. This is in stark contrast to conventional manufacturing techniques where a large portion of the material is wasted, making Apium’s FFF technology the favourable manufacturing tool for small series production, prototypes, and custom parts.
Despite the cost benefits of the FFF process, PEEK itself is a high-priced material, which limits its use in manufacturing companies. Apium sought to address this and further enhance the economic efficiency of its additive manufacturing solution.

Cost Savings Through Supply Chain Management

By implementing lean supply chain management Apium is now able to offer its PEEK filament at a reduced price.
“The response towards our PEEK filament immediately after the market launch two years ago was astonishing. However, we quickly saw that the material should be cheaper to encourage its use within industries seeking to fabricate prototypes, spare parts, and small batches. Together with our supplier Ensinger GmbH, we performed a meticulous assessment of our SCM, which has resulted in the optimization of the manufacturing and delivery processes of our PEEK filaments.”
As a result, Apium was able to lower the price of PEEK filament by around 26% and is convinced of the ability to expand the fields of applications for PEEK 3D printing due to higher economic efficiency.

The Launch of Apium’s P155 High-Performance Polymer 3D Printer

The new Apium P155 can process PEEK as well as all other high-performance polymers from Apium and is equipped with optimized processes like the improved Apium Controlling Software and an optical process control to increase the print quality.
“To celebrate the delivery of our Apium P155, we are running a promotional offer, where for the next month, our customers will receive a discount of 25% to the already reduced price of our PEEK filament”, explained CEO Tony Tran-Mai.
Thanks to the savings made from the SCM optimization process and the current market situation the 500g spool of Apium PEEK filament is now available for 333€. Through the temporary discount until the 28th of February, caused by the launch of the Apium P155 3D printing system, the filament is available for 249€ and can be purchased online at www.apiumtec.com/de/shop/.

Leveraging 3D Printing technologies with a strong industrial partner

In recent times, there have been concerted efforts at advancing the technical and economic promises of 3D printing technologies deep into the manufacturing industry. The development of 3D printing technologies in order to meet manufacturing requirements is still an ongoing process even after over 30 years of introduction as an alternative manufacturing tool. Although significant technological progress has been made to bring the powder-based systems as close as possible to mainstream industrial applications, there still remains some work to be done to manage the entry of the filament based or liquid based (photo-polymer) systems. Whilst these systems have been proven capable for the processing of polymers into functional engineering parts, the influential role of big industry to promote their manufacturing relevance is still lacking.

Materials remain the most decisive aspect of additive manufacturing (AM) or 3D printing technologies. Apium Additive Technologies, an innovations-oriented company based in Karlsruhe, has distinguished itself as a key global solutions provider of 3D printers capable of processing high temperature polymers such as polyethertherketone (PEEK). PEEK is a polymeric material with such cherished attributes that it is especially sought for use in high end applications in the fields of medicine, aerospace, vacuum systems, electronics & semiconductor as well as systems where light weight, high specific strength and corrosion resistance are required. The technology which Apium has developed is based on the fused filament fabrication (FFF) technology. Apium’s technology is unique as it considers the materials science based governing principles which make it possible to process PEEK to qualities fit for industrial applications.

Apium’s FFF 3D Printing technology offers high processing efficiency, easy operating conditions, low cost maintenance and the access to fabricate functional parts from high temperature polymers.

Competence centre Apium Additive Technologies GmbH
In 2014, Indmatec GmbH the forerunner to Apium Additive Technologies GmbH was founded to provide 3D printing based technology which offers industry an access to high temperature polymeric materials. To reach new markets and to make a welcome entry to the international 3D printing space, Apium was founded in 2016. Apium’s technological success rests on its team of engineers, scientists, sales and marketing personnel and the highly talented interns who work tirelessly to ensure that innovative solutions to pressing challenges in the unique processing field of high temperature polymers are brought to end-users. The first commercial FFF 3D printer capable of printing PEEK was launched in 2015 creating a strong global interest in Apium’s technology. Due to the pioneering work Apium as done on 3D printing of PEEK its operating facility located in Karlsruhe now serves as a competence centre for generating knowledge regarding FFF 3D printing of high temperature polymeric materials such as PVDF, POM-C, Ultem (PEI) as well as PEEK filled with carbon fiber. The leadership Apium brings to the additive manufacturing industry is without doubt at least in the fld of high performance polymeric materials. Its clientele is broadening beyond key engineering sectors now to medical, industrial R&D groups as well as university groups intent on taking advantage of the manufacturing freedom offered by 3D printing technologies to process PEEK to geometries hardly possible to create using traditional manufacturing methods.

Materials at Apium
Apium’s flagship product, Apium PEEK 450, offers unique mechanical, chemical and thermal properties. PEEK has many advantages over other polymers and is able to replace industrial materials such as aluminium and steel. It’s use in structural applications makes possible reductions in the total weight of systems where mass is a critical efficiency factor especially with respect to energy and agility. Compared to metals, PEEK polymer allows a greater freedom of design and improved performance. Its wide range of operating temperatures (-196°C to 260°C) plays a significant role in applications involving high mechanical and dimensional stability. For the reasons alluded above, PEEK greatly sought in the oil & gas, aerospace, automotive, semiconductors as well as electronics sectors. In the medical sector, due to its biocompatibility, sterilizable nature and tolerance towards radiation in radiology applications PEEK is a choice material for implant and surgical tools.

Apium’s fluoropolymer; Polyvinylidene fluoride (PVDF), is a medium viscosity homopolymer. It exhibits good stability under thermal, chemical or ultraviolet conditions. PVDF is structurally stable up to 149 °C operating temperatures, resistant to most chemicals (solvents) and is generally unaffected by long-term exposure to ultraviolet radiation. Together with these reasons as well as its high resistance to friction especially in wet environments, PVDF is the material solution for challenging deep water applications in the oil & gas industry.

Apium’s Polyoxymethylene co-polymer (POM-C) is a high strength and modulus material lending this material its particularly high resistant to impact and fatigue. Due to its relatively light weight (density is about 6 times and 3 times less than for steel and aluminium respectively), it is often used as a replacement for metals.

 

Apium P 155 high-performance materials 3D printer

Apium P 155 high-performance materials 3D printer

3D printers
Apium’s 3D printing technology guarantees the processing of high temperature polymeric materials. The printer technology currently in its 3rd generation is embodied in the P series 3D printers. These printers have been designed to give a certain technical appeal Apium’s key market segments namely R&D groups at Universities and companies, low volume manufacturing groups and real operating conditions prototyping groups. The operating attributes of the P-series machines make it possible to reach HotEnd temperatures of 520 °C, bed temperatures of up to 160 °C and to alternate across different materials by the mere change of print head in an easy fashion. These attributes ensure that the: (i) part is firmly adhered onto the print-bed, (ii) surface quality of printed parts meet key engineering applications, (iii) mechanical properties of the printed parts compare with materials based bench-marks and (iv) printing process is cost efficient. Apium’s controlling software provides an operator advantaged access to the entire printing process where permutation of printing parameters is possible for the determination of process – property relationships for different printed materials. Additionally, the system performance of Apium’s 3D printers leverages on the materials science which governs polymer processing. This involves an understanding of melt behaviour, phase transformation and the thermo-mechanical influences inherent to the printing system. Apium’s 3D printers deliver the state-of-the-art in FFF 3D printing of high temperature polymers.

Print-services
Apium offers 3D print services for PEEK, PEI, POM-C and PVDF materials. The industrial relevance of these materials cannot be understated therefore Apium is providing a uniquely rare opportunity for industrial groups to fabricate their parts; irrespective of design complexity. Such an opportunity refines the learning-curve in the field of additive manufacturing and gives machine developers and operators the chance to bench-mark as well as better meet industry based challenges.

Trainings
The practice based knowledge as well as competence being created at Apium is organized in the form of training packages. These trainings typically planned for engineers, technicians and management level personnel allow for the transfer of Apium’s additive manufacturing technology to practitioners in industry. By this Apium is able to inform its clients about best practice in the field of AM and to better understand the applications relevance of Apium’s technology.

 

 

Powerful production partners are key to success
Apium’s production partnership with a global first-rate company like Heidelberger Druckmaschinen AG (Heidelberg) makes possible the creation of its industry level P220 series of 3D printers.

Taking advantage of Heidelberger Druckmaschinen AG’s Smart Factory platform which is supported by its highly qualified interdisciplinary teams, Apium is assured that its P220 series 3D printers will meet safety, control, performance and productivity standards of distinction.

On the materials side, Apium’s partnership with Ensinger GmbH gives a firm guarantee that its filaments are of the highest technical quality meeting both physical and chemical specifications needed for the FFF technology. Ensinger GmbH brings along several years of experience in the field of polymer compounding and extrusion. This way, the materials development work at Apium for new FFF 3D printing solutions can be commercialized and provided to industry at economically attractive conditions.

Rapid manufactured PEEK for the chemical process Industry

Introduction

There persists some level of ambivalence in industry regarding the deployment of 3D printed parts for end-use applications. A key reason for this hesitation is the notion that 3D printing technology is still not considered ripe as a manufacturing tool. Even for high-end metal processing systems industrial attitude is still one of caution; caution driven by different kinds of factors including but not limited to media reports, material, metrology, quality assurance, access to the technology and the general lack of comprehensive data to support the technology.

It therefore goes without saying that there is a need to provide industry with supportive data as well as demonstrated manufacturing ability to 3D-print parts that meet design specifications.

Industry needs to accept that additive manufacturing tools such as 3D printing technologies are instruments technically endowed to handle mainly tasks involving low volume rapid manufacturing and mass customization. The key advantage of enterprise 3D printing is to produce the first real parts at low cost and also shorten the overall time from concept design to part deployment.

In view of these facts, materials as well as part quality must play a central role in our quest at persuading industry to embrace the manufacturing-preparedness of 3D printing technologies.

The ability to 3D print materials; such as PEEK, which meet extremely demanding engineering requirements (high mechanical toughness, corrosion resistance, wear resistance, chemical inertness and UV resistance) is a unique manufacturing opportunity. Functional and structural part designs which have geometries of complexities difficult to create using conventional manufacturing methods (such as injection moulding and CNC milling) can now be fabricated using 3D printers employing the barest minimum production steps.

 

Practice based examples

The diagram shown in Figure 1a, b illustrates a PEEK part fabricated using an Apium P 155 3D printer then fitted with metallic connection nozzles in a post print step. This P 155 3D printer has been especially designed for processing high temperature polymeric materials. Its mechanical performance together with the software that makes it possible to generate and precisely execute the printing plan have been extensively tested to guarantee PEEK parts of high quality. 

(a)

(a)

(b)

(b)

Figure 1. PEEK part manufactured using fused filament fabrication (FFF) 3D printing technology (a) view of as-printed sectioned part., (b) closed part view. (Height: 95 mm, max. Diameter: 40 mm)

The PEEK part in Figure 1 is a prototype multi-channel mixing column printed in section to reveal internal features. It has a surface structure (Figure 2) as well as internal walls characterized by fine interfaces created by the layer on layer deposition of PEEK melt on stress-free surfaces of solid PEEK. Edge zones of the PEEK part are well defined confirming the nature of fluid mechanics that precedes the melt solidification process. Clearly the phase transformation processes namely nucleation and growth of crystalline domains in the melt, the solidification rate as well as the rate of heat dissipation from the solidified PEEK structure are adequately controlled during the printing process thus making possible a high quality printed PEEK part.

Figure 2. Magnified image of part in (Fig. 1): a fluid mixer fabricated out of PEEK material. Note the fine surface contrast created by the layer on layer deposition of PEEK material. 

Figure 2. Magnified image of part in (Fig. 1): a fluid mixer fabricated out of PEEK material. Note the fine surface contrast created by the layer on layer deposition of PEEK material. 

The PEEK parts shown in the following Figures 3a-d were also printed using an Apium P 155 3D printer. The surface qualities of these parts attest to the engineering stability and reliability of the P 155 printer. All the parts represent functional components applicable in the chemical technology sector.  

Role of 3D printing in the chemical industry

Computer simulation efforts in the areas of fluid dynamics, rheology and chemical process studies have in the past 30 years dominated developmental activities in the field of process engineering. Whilst this approach brings with it valuable amount of cost savings on financing and time, there remains a need to physically model unit operations or unit processes in order to overcome design based constraints irresolvable using computer aided tools. For this reason process engineers still resort to building pilots and miniature plants to test their designs in real life circumstances. 

Figure 4. Gear pump system 3D printed from PEEK, housing is 3D printed from polyamide (PA6).

Figure 4. Gear pump system 3D printed from PEEK, housing is 3D printed from polyamide (PA6).

This is where a manufacturing tool like 3D printing can play a profoundly decisive role. By 3D printing the hardware needed to build a miniature or pilot process plant engineers can save huge amounts of time, computational effort and investment cost into plant development. Plant elements (Figure 4) such as separation units, compressors, storage tanks, pipelines, pumps and valves can be 3D printed at small scales and tested as real functional parts in plant development projects. Joints, connection points or locations where different parts are coupled can be eliminated simply because it is possible to build the entire contraption of plant elements in one piece using a 3D printer.

 

For example PEEK; a material with properties which make it an attractive technical asset in chemical process plants can be used for reaction vessels loaded under extreme pH environments. Its structural stability also makes it attractive in oil & gas applications. The fact that 3D printing technologies are today capable of fabricating metallic parts, technical ceramic parts and high temperature polymeric parts support the unique development of this manufacturing tool and the outstanding opportunities provided to industries to design highly specialized parts with the hope that their manufacture is possible.

Some practice relevant data

Data provides the confidence needed to anchor 3D printing technologies as a mainstream operation in the field of manufacturing. However the mass of technical evidence needed to inject trust for 3D printing in industrial applications is far from adequate. Some of the several reasons why this is so are because (i) machine producers are not disclosing the entire information about the quality of parts fabricated from their 3D printers; often only data capable of inducing commercial success is published (ii) majority of research based groups using 3D printers in their labs are not testing printed parts for performance rather they are focused on prototyping to meet form and geometric requirements (iii) a big section of the 3D printing user group are composed of players from the maker-community acting as hobbyists often with little or no access to test facilities needed to give credibility to the valuable development work going on in the field of 3D printing. Thus the fact that some machine manufacturers are secretive about test results from parts fabricated from their machines raise questions about quality assurance, reproducibility of properties in 3D printed parts, reliability of the 3D printing process and of course on the existence of measurable parameters for bench-marking 3D printed part integrity.

In the past 5 years there has been an interest within the field of additive manufacturing to explore the processability of materials used in safety-critical applications. Fibre-reinforced polymeric materials, composites materials containing nano-materials such as carbon nanotubes, advanced materials such as shape memory alloys and materials used in human implant applications such as titanium-6-Al-4-V (Ti6Al4V) and PEEK are key amongst such materials. For a relatively new manufacturing technology like 3D printing, the threshold for acceptance is understandably set high because there is suspicion, caution and a general sense of uncertainty towards new habits, methods or processes in a rather conservative industry like the manufacturing sector. That said, experimentally generated data which allows for the interpretation of the performance of 3D printed part needs to be published.

In Figure 5 the mechanical properties of PAEK (PEEK, PEKK are chemical derivatives of PAEK) parts fabricated using different manufacturing methods are presented. Generally the industry bench-mark for polymeric materials is injection moulded part datasets. The plot in Figure 5 shows that there are clear differences in mechanical properties where the injection moulded part as well as the FFF 3D printed part exhibit superior strength.  

Figure 5. Plot showing the tensile strength and strain for PAEK parts fabricated using different manufacturing methods.

Figure 5. Plot showing the tensile strength and strain for PAEK parts fabricated using different manufacturing methods.

In vacuum technology where chemical inertness, high strength and outgassing are critical issues, PEEK has found application in the areas of: sealing, gaskets, material for low load bearing structural components and as substrate for active agents. In Figure 6 outgassing test results for 3D printed PEEK parts studied under vacuum condition are presented. The results indicate outgassing rate of 5x10-7 mbar l/cm-2 s-1 after 18 hours in vacuum. When baked for 12 hours at 150 °C prior to testing in vacuum condition, the 3D printed PEEK part exhibited outgassing rate of 4.1x10-11 mbar l/cm-2 s-1; a value falling well within the ultrahigh to extremely high vacuum range.

Residual gas analyser (RGA) scan on the PEEK samples to determine the kind of molecules being outgassed revealed the main gas species observed were hydrogen water and carbon dioxide; most likely from the hot filament in the RGA.

Figure 6. Test result for outgassing of 3D printed PEEK parts under vacuum condition.

Figure 6. Test result for outgassing of 3D printed PEEK parts under vacuum condition.

Conclusion

There is a place for 3D printing/additive manufacturing within the chemical process industry; we need to work at identifying this niche. In the medical sector 3D printing tools are already being used for patient-specific implant production applying data from MRI or CT scans of the patient as input to the 3D printer. Can computer aided models of process plants be re-sized and 3D printed? Can we enhance our digital workflows with design features and attributes which will make it possible to 3D print models of plants and test run the plants? Can 3D printers be used for spare-part fabrication to keep our aging plants running or for fabricating newly developed component designs fitted to improve on plant performance? The authors believe there is a practicable opportunity to do new things in plant design, operation and optimization using 3D printing technologies.

 

Acknowledgement

We appreciate University of Applied Sciences Merseburg – Germany for the mechanical test data on FFF 3D printed PEEK and Mr. Andy Stallwood of Diamond Light Source Ltd UK for the vacuum tests.

Authors: Uwe Popp, Julian Scholz, Brando Okolo

The next industrial 3D printing revolution for high performance polymers using FFF technology

Often times growth is tagged along by new responsibilities, new challenges, new opportunities and also the chance to make changes which truly reflect growth. Indmatec at the onset of its growth stage is going global as “Apium Additive Technologies GmbH”. Indmatec’s global leadership and pioneering role in the field of high temperature polymeric materials processing using Fused Filament Fabrication (FFF) 3D printing technology is now embodied in Apium. To consolidate this technological leadership Apium has partnered with Heidelberger Druckmaschinen AG; an indisputable platinum-grade leader in industrial 2D off-set printers, to run its patented technology on a new generation of 3D printers for the enterprise market. This partnership endows a quality seal on Apium’s 3D printers, allowing for the deployment of innovative work crafted by the team at Apium to FFF 3D printers that deliver at the industrial scale. To secure our value chain within the additive manufacturing sector, our materials business unit is now leveraged by our partnership with Ensinger GmbH; a champion in the global scene of polymer extrusion. This materials driven partnership embodies the core of our business philosophy where a deep understanding of materials sets the tone of 3D printers.

For two years our team has focused on harnessing the critical role of materials science and engineering and led an agile effort to design FFF 3D printers that meet your manufacturing requirements. At the 2016 TCT powered Formnext fair “Apium P155” and “Apium P220” will be launched as the new generation FFF 3D printers for fabricating high performance polymeric material parts which meet your applications requirements.
Visit us at Formnext from 15th to 18th of November in booth 3.1 B40C to witness demonstrations of state-of-the-art premium grade polymer processing using FFF 3D printing technology.

Apium’s next generation high performance polymers 3D printer “Apium P155”

Apium’s next generation high performance polymers 3D printer “Apium P155”

Successful WECONOMY Competition

WECONOMY is a competition for the most innovative start-ups in Germany founded by Wissensfabrik – Unternehmen für Deutschland e.V.. With about 120 members from different branches, they support german companies as well as start-ups and connecting them to established enterprises.

With their annual competition WECONOMY, they offer newcomers and young companies the possibility to present themselves in front of a jury, consisting of managers, experts and founders. After being judged for their grade of innovation, market potential, customer value and founders, the winners will be chosen.

Indmatec is proud to announce being one of the WECONOMY winners!

This year Indmatec is one of the nine start-ups that won the WECONOMY event and is now fortunate to gain the expertise and know-how of top managers from Bosch, Daimler, KPMG, BASF and many more over the next weeks and months. Knowledge for marketing & sales or strategies in growing are part of the support together with coaches for workshops to build a powerful team, mentoring managers and an excellent network to give the company the next boost. Indmatec is looking forward to implement all the new ideas and recommendations they will receive as a part of the prize for winning the competition.

 

Impressions of a get-together with top managers, talking about the possibilities, which come along with a 3D printer that uses high performance polymers:

Test Data of 3D printed PEEK and its outstanding Properties

Since additive manufacturing methods have been used more and more in the past few years, the biggest barrier that holds the different methods back from being used in industrial applications have been the limited materials that can be processed. For example, for the well-known Fused Filament Fabrication (FFF), which is also the most used method by many private users, there just have been simple polymers like ABS that can only be used for models and not for actual industrial parts.

Now combining the high performance polymer Polyetheretherketone (PEEK) with additive manufacturing like FFF, it can be used for several different applications in industries like automotive, oil & gas, aerospace, medical or semiconductors to produce complex geometries or individual parts with less use of material.

This variety of different applications is made possible by the great properties of PEEK. In fact, PEEK is one of the most durable polymers and can be compared to metals like aluminum. Due to its very high melting point of 343 °C (649 °F) and a using temperature range from -196 °C (-321 °F) to 260 °C (500 °F) it can be used in a lot of extremely demanding environments, e.g. powertrains in automobiles. With its high temperature resistance, lower weight high wear resistance and chemical inertness, the polymer can replace metals in those demanding environments to save weight and make aircrafts or automobiles more efficient. PEEK benefits from its structural endurance up to pressures in the order of 200 MPa (~29000 PSI), too. Ideal for engines or sealing parts. Because of its strength, PEEK can also be used in lightweight constructions, processed with the FFF method that can easily make honeycomb-like structures.

One of the obstacles, why 3D printing still is not used for industrial manufacturing in a big way is the lack of experimentally generated data. These data that clearly demonstrate what 3D printing with high performance materials is capable of. To overcome the mistrust, insecurity and caution that comes in general along with new technologies, data that supports this technology has to be published.

Test Data like Figure 1 that shows a comparison of the tensile strength and strain for PAEK (PEEK and PEKK are chemical derivatives of PAEK) parts fabricated using the different manufacturing methods selective laser sintering (SLS), injection molding (IM) and fused filament fabrication with a Indmatec HPP 155 printer (Indmatec FFF). Generally, the industry bench-mark for polymeric materials is injection moulded part datasets. Regarding this, the plot in Figure 1 shows that there are clear differences in mechanical properties where the injection moulded part as well as the FFF 3D printed part exhibit superior strength. 

Figure 1: Tensile strength and strain comparison

Figure 1: Tensile strength and strain comparison

Regarding test data like this, FFF 3D printed PEEK has the ability to be used in industrial applications. Together with its properties, the material is suitable for applications where materials are sought that can withstand their demanding environment. Combined with 3D printing it enables the different industries to use this high performance polymer in a material and cost lowering way. Individual, complex parts can be processed easier and with less effort.  

3D printing and additive-manufacturing PEEK parts for the oil & gas industry

The erroneous notion has sometimes been that any 3D printer can be used for fabricating just about any solid object conceivable. This however is not true; in fact there are at least 8 different kinds of 3D printing technologies. Each of these technologies is conditioned for 3D printers designed for a specific material class thus delivering different mechanical performances for parts fabricated.  Although still relatively a young fabrication method, an important news about 3D printing technologies is that it now has about 30 years of practice-based evidence to prove that it has evolved to become a tool for the production of highly complex, high value, engineering critical parts. For instance 3D printing technologies have been adopted by the air craft industry for the manufacturing of different kinds of components including safety critical parts used in passenger airlines. Likewise in the medical sector it is also now being used for the fabrication of patient-specific implants used for long-term application in human medicine. The entry level for 3D printing technology in the various high-end economy leveraging industries is of course understandably different but there are hallmarks to follow. 

The material PEEK (poly ether ether ketone), for example, already has a technical history in the oil and gas sector for its various valuable attributes. PEEK brings along properties which make it suitable for use in extremely demanding operating environments. Some of these properties are:

-Its stable mechanical performance in the temperature range -196 °C (-321 °F) to 260 °C (500 °F)
-Its structural endurance up to pressures in the order of 200 MPa (~29000 PSI)
-Its high anti-corrosion properties ensuring mechanical stability and surface dynamics are fully retained in both seawater and aromatic NORSOK               hydrocarbon fluid environments
-Its technically marginal (~25%) loss in tensile strength upon exposure to 100% hydrogen sulfide gas under relatively high temperature (220 °C) and pressure (~4.5 MPa) conditions.


These properties make it attractive to use PEEK for components supporting down-hole equipment such as sealing systems, fasteners, gas separation systems, gears, impellers, plugs, tubes and housings.

Only recently has it been possible to additive-manufacture PEEK parts using the so-called fused filament fabrication (FFF) 3D printing technology. The 3D printer developed for this process is portable and equipped with easy to operate features. Such a 3D printer can be installed at onshore, offshore or remote locations where oil and gas operations are highly time-critical. An obvious advantage being that the time to realizing maintenance based goals can be significantly shortened; especially for goals that currently rely on deployment of parts from relatively distant warehouses or supplier locations to sites where they are needed in order to urgently keep production going without interruptions. Clearly a 3D printer on-site can empower location-based crew to rapidly manufacture replacement parts or supplementary parts so as to maintain operating and production levels.

Figure 1 shows oil and gas relevant 3D printed PEEK parts.

3D Printing Application with PEEK for the Automotive Sector

In automotive sector, materials are needed that are not just durable, to improve the reliability of a vehicle, but also have to bring several properties with them, like chemical inertness, temperature resistance or wear resistance. Thereby it is guaranteed to have more durable parts with less maintenance. On the one hand it is a big plus for the consumer, because he can save costs, on the other hand also for the manufacturers who will have a higher quality in their automobiles due to the fact that parts have to be replaced less, which results in a better image.

To this point metals have been the materials of choice, since they combine all required properties. However, a big disadvantage is the weight. With less weight fuel can be saved, which results in reducing CO2 emission. A thought that appears more often these days.

PEEK replaces metals

This is possible thanks to a high performance polymer called PEEK (Polyetheretherketone). Due to its semi crystalline structure, it can be used very well above its glass transition temperature of 143°C and fits just perfect in the automotive sector where parts in the powertrain and motors have to operate at 150°C or more, most of the time. PEEK parts can also be used with higher temperatures, due to its melting point of 343°C and a service temperature up to 260°C.

Besides the mechanical resilience of PEEK, the polymer is chemical inert. This is important for parts in the powertrain, which shouldn’t receive damage from the different fluids, like oils or fuels. Applications are for example wear parts that were made out of metal before. Using PEEK instead of metal, the weight of a part can be reduced by up to 70%, which results in a total saving of 1-2% of fuel. Furthermore, the wear of PEEK parts is 25-75% less than the one for metals; the parts are also more resistant facing too little lubricant. Another advantage compared with metals is the reduction of noise.

3D printed PEEK parts

The most effective manufacturing method for PEEK is 3D printing. Hereby, parts which are impossible to be produced with conventional methods, due to their complex geometries can be fabricated. Much more important is the potential to save on material. For example, in the FFF (fused filament fabrication) technology a polymer wire, the filament, is being melted with a nozzle and laid down layer by layer. Doing so, only the material that will be in the part is used. Compared to CNC milling, where up to 90% of the used material will become shavings, depending on the application, 3D printing reduces the material costs significantly.  

 

Although the FFF method cannot be used for mass production adequately, it will provide e.g. the research and development with prototypes without big efforts. In addition to that, individual parts can be produced and small batches are possible, too. Figure 1 and 2 are showing 3D printed PEEK parts that can be installed in powertrains. Both parts are manufactured by an Indmatec HPP 155 3D printer.

Figure 1: Cone gear

Figure 2: Sealing rings

The main benefit of gears made out of PEEK is the wear resistance towards the forces, which appear between the gears. PEEK sealing rings hold the advantage to be resistant towards fluids in automobiles, making them more durable.

A decisive criterion in producing functional parts with additive manufacturing methods is if the strength of those parts is comparable to conventional manufactured products. Figure 3 shows a tensile strength comparison between PEEK manufactured with selective laser sintering (SLS), Indmatec’s FFF and powder injection molding (PIM).  In this connection, it’s noticeable that the FFF technology is quite in the range of injection molding, regarding their tensile strength. The tests have been made in X/Y direction, due to the layers the tensile strength in Z direction is about 30% lower. 

Figure 3: Tensile strength comparison

Besides the possibility to fabricate complex geometries with 3D printers, parts in lightweight construction can be produced too, as figure 4 shows. With injection molding those constructions wouldn’t be possible. Thanks to the honeycomb structure, the strength is about the same as the strength of a solid printed part, but with a significant reduction regarding weight and material. 

Figure 4: Lightweight angle

3D printing in combination with high performance polymers, like PEEK, could be an alternative to manufacturing metal parts in the automotive sector, to make vehicles more efficient and to realise an idea towards the final product in a simpler way.

High performance polymers for automotive applications>

Positioning 3D printing as a manufacturing tool

In the past 10 years there has been a keen interest by industry towards the application of rapid prototyping methods in product development. By extending this interest to new fabrication methods such as 3D printing technologies, industry is intent on adopting new pathways in order to redefine its future. To chart these pathways, practice based testing of 3D printing technologies is becoming a strategic activity in a growing number of industrial establishments. Some of the tests reveal data which has given industry the confidence to engage 3D printing technology as a rapid manufacturing tool. The ability to stably process metals, composites as well as high performance polymer materials using additive manufacturing tools opens a unique opportunity for industry to do new things in the field of manufacturing. Particularly within the past 5 years fiber reinforced polymers as well as high to extreme temperature polymers such as PEEK (Figure A) have received special attention in a range of industries for different kinds of reasons. Some of these reasons border on energy conservation, light-weight construction, thermo-mechanical performance, biocompatibility, chemical inertness or on electrical properties. Therefore materials are at the core of the situation pulling industry towards additive manufacturing. Polymers are without doubt the only class of materials that can be easily processed at relatively low energy cost, composited using different kinds of other materials and used to meet different kinds of requirements in engineering and technological applications. For this reason there is a need to intensively explore the processibility of polymeric materials using additive manufacturing tools.

Figure A. Fused filament fabrication (FFF) 3D printed parts from different polymericmaterials

 

Rapid manufacturing is guided by the philosophy of manufacturing functional parts at the shortest possible time. Together with the freedom to fabricate parts which have complex geometries rapid manufacturing also allows for mass customization within industry. Whilst processing time/unit-part remains a challenging aspect of rapid manufacturing when compared to conventional manufacturing methods like injection molding processing (Figure B), it goes without saying that 3D printing technologies are inherently designed for small series production and parts which have highly complex forms.

Figure B. Cost benefits compared: Additive Manufacturing and Conventional Manufacturing
 

In other words there now exists a market for enterprise based 3D printing or additive manufacturing. In the materials market producers are expanding their portfolio to include additive manufacturing-designed materials in order to meet requirements in tool development, molds, die and support structures used for practical engineering activities. These materials are relatively more expensive than those (such as ABS, PLA, photopolymers) historically used in rapid prototyping 3D printing processing. The performance value of these materials is high and the 3D printers capable of delivering these materials to industry are also relatively more expensive than those used for hobby or purely prototyping purposes.

The processing requirements for high performance materials can be very stringent. For example industry-established thermoplastic materials such as PEEK are not easy to process. Amongst the current selection of 3D printing technologies, only Fused Filament Fabrication (FFF) and selective laser sintering (SLS) methods are technically capable of processing PEEK. These processing methods are markedly different hence producing different effects on the processed material in such a way that the printed parts from each of the methods are structurally different especially at the microscopic level thus lending parts produced from each method different mechanical properties (Figure C). The technical or scientific explanation for this property difference is not trivial but can be traced to the thermal load imposed on PEEK during laser processing as against mere melting and solidification for the FFF method. This kind of discrepancy especially in terms of part property can significantly drive market preferences. 

(a)

(b)                                                                                                                          (c)

Figure C. (a) FFF 3D printed PEEK part (b) Tensile test PEEK sample in test machine (c) Tensile strength and Strain plotted for SLS produced PEEK and FFF produced PEEK.

We now have about 30 years of evidence indicating that 3D printing technologies work. Building on this fact, the authors see a very bright future for rapid manufacturing.  It fits well within a landscape where lean production lines, short supply chains, logistics and warehousing operations are changing. Rapid manufacturing as well as the tools that support it fit quite well with the school-of-thought Production-on-demand making a case for its positioning within an Industry 4.0 sector.

 

Acknowledgement

We appreciate Technical University Delft and University of Applied Sciences Merseburg for the mechanical tests data.

 

Contact

Brando Okolo (PhD)

Indmatec GmbH – Karlsruhe – Germany / brando.okolo@indmatec.com

Indmatec 3D printed PEEK for applications in vacuum technology

In the field of vacuum technology outgassing materials are forbidden because they bring along attributes which make it difficult to achieve desired vacuum quality. Outgassing materials release molecules in gaseous form which can contaminate prime components or diffuse into machine parts modifying them against their designed purposes.

Metals have primarily played a key role in the design of parts destined for applications in vacuum technology because when well treated they do not outgas. Most polymers however do outgas. This is an inherent feature in polymeric materials because they are essentially made from chemical species with tendencies to evaporate under appropriate temperature and pressure conditions.

One of the attributes of PEEK is its low outgassing behaviour even at relatively high temperatures.

Vacuum tests conducted on PEEK parts fabricated using Indmatec 3D printing technology and Indmatec PEEK filament material showed an outgassing rate of 5x10-7 mbar l/cm-2 s-1 after 18 hours in vacuum. To bring this data into context, fact is that the PEEK material in its as-3D printed state meets the material requirement for high vacuum applications. When baked for 12 hours at 150 °C prior to testing in vacuum condition, the 3D printed PEEK part exhibits outgassing rate of 4.1x10-11 mbar l/cm-2 s-1; a value falling well within the ultra high to extremely high vacuum range.

This quality of data together with PEEK’s resistance to radiation damage extends Indmatec’s 3D printing technology to applications in space exploration where light-weight materials capable of enduring the demanding requirements for research in space environment are sought.


Vacuum technology applicable PEEK parts fabricated using Indmatec 3D printer

Contact:

Brando Okolo (PhD)

brando.okolo@indmatec.com

Acknowledgement:

We appreciate Mr. Andy Stallwood of Diamond Light Source Ltd for the vacuum tests.

Coupling PEEK to FFF 3D Printing Technology

Author: Prof.Dr.Brando Okolo

PEEK (Polyetheretherketone) is a semi-crystalline thermoplastic polymeric material. Its introduction into the market as an industrial material has revolutionized materials choice by engineers serving across a wide range of sectors. 


Here are some attributes of PEEK giving perspective on its application areas:

- Thermal stability up to 250°C (it does not suffer structural deformation hence can be used in water boilers or low pressure steam systems without change in its physical properties; its melting temperature is 343°C.)

- Good wear and abrasion properties (can be used in bearing, sliding surfaces and systems where surfaces in relative motion must maintain dimensional tolerances) - better than titanium and steel.

- Good creep properties (can be loaded under static loading conditions for a long time without permanent deformation).

- Very low moisture absorption.

- Repeatedly sterilize-able using steam (hence eliminating and/or preventing the survival of germs, bacteria and other microorganisms).

- Bioinert/biocompatible with flexural moduli similar to that of human bone than any other implant material hence less stress shielding and better bone resorption.

- Chemically inert therefore can be used in harsh corrosive operating fields providing attendant saving on anti-corrosion treatment.

- It has a density that is at least 5 times less than more technical metals but capable of withstanding mechanical loads inherent in most engineering operations.

- Good electrical insulation.

- Holds a V-0 flammability rating (that means it stops burning within 10 seconds once inflamed and drips hot particles which are not inflamed).

- PEEK is approved by the FDA for food and contact applications.


Some established application areas of PEEK:

Aerospace:

- Clamps and brackets for structural parts.

- Tubing.

Electronics:

- Laser printer parts where heat resistance, high strength, wear and torque resistance (gears and bushings) are required.

Energy:

- Seals and gaskets in oil and gas applications due to its stability at relatively high temperatures, resistance to corrosive influences, stability at pressures up to 200 MPa and attendant gains in component lifetime under wear and pressure loading conditions.

Medical:

- For implant in orthopedics as support structures in bone fracture, cages and rods for spinal implant.

- For prosthetics in dentistry as crowns and bridges inserted as dental discs.

Automotive:

- For gear systems where they are known to produce up 50% reduction in noise, vibration and hardness (NVH).

- Parts for vacuum pumps due to their low wear, dampening and chemical inertness.

Light weight engineering:

- No lubration under tribological loading conditions as in bearing systems.

- About one-fourth lower moment of inertia compared to metallic structural materials.

- Has up to twice the operating lifetime compared to steel based bushings.


Facts:

We now have a light weight (about 70% lighter than most technical metals) material capable of replacing metals in some key engineering applications because its thermo-mechanical properties are applications competitive. Implementing such a material in industry could result in huge financial amount of savings in energy and reduction in carbon footprints.

- This material is expensive compared to Aluminum and other technical polymers though its economic benefit as an engineering material outweighs its entity price. Most PEEK materials used in the industry are processed using injection moulding or machined (drilling, milling, cutting) using computer numerical control (CNC) methods. These processing methods are accompanied by unavoidable material waste generation. Waste (even recycle-able waste) is bad economics for any industry.

- If PEEK could be processed using 3D Printing technologies the following will happen: (i) no waste generation, (ii) ability to mass customize the part - e.g. patient-specific implants in the medical sector (iii) low investment on machine and operatpr training making it easy for small and big businesses to benefit.

- The most affordable 3D printing technology - FFF Technology- can now be used for PEEK.

- Indmatec GmbH, located in Karlsruhe Germany, extruded raw PEEK into a high quality filament form and has proven the technical possibility of 3D printing PEEK using FFF technology. They also offer the technical support tp help you 3D print any technical thermoplastic material you wish to have in your products.

 

Indmatec GmbH 3D Printing PEEK using FFF technology

Author: Prof.Dr. Brando Okolo

Most commercially available fused deposition modeling (FFF) 3D printers operate with extruders capable of processing material at up to 300 deg. C. For most high performance polymeric materials (especially thermoplastics) with melting points at above 300 deg. C such as PEEK, PTFE, PPSU this means that they can not be used for fabrication of parts using FFF 3D printers. The introduction of an all metal hot-end extruder capable of attaining temperatures up to 400 deg. C opens the chance to apply more materials in industry using this 3D technology.

Small and Medium scale Enterprises (SME’s) drive the processes which make countries like Germany have a global scale industrial-edge. This segment of the economy deserves unhindered access to 3D printing technologies. Unfortunately the prices of industrial scale 3d printing facilities are prohibitive making it an irritating reality for SME’s seeking to incorporate 3D printing in their workflows.

Indmatec’s work on the most affordable 3D printing technology (FFF 3D Printers) makes it possible for SME’s to buy 3D printers, select from a wide range of technical polymers and receive the most qualified advise on 3D printing for their business.

Indmatec’s demonstration of the technical ability to print a material like PEEK using FFF 3D printers is a critical step forward for industry. See here https://www.youtube.com/watch?v=ZaFYimxFPmM&feature=youtu.be

Get a date with Indmatec GmbH then make that key decision to move your business forward.

3D Printing in Your Dental Practice: A Cost Saving Solution for Orthodontists

Author: Prof.Dr. Brando Okolo

The development of invisible orthodontics has opened new avenues for ensuring that patients overcome the stigma of being seen with metallic components in the mouth. While traditional orthodontics (both visible and invisible) generally may induce a great deal of pain, injuries, mouth sores and discomforts of various degrees caused by the wires used for bracing the teeth, there now exist brace-less orthodontics which offer far reaching patient satisfaction. Brace-less orthodontics, so called clear/transparent tray aligners, also make it possible for patients to receive treatments on crooked teeth, teeth spacing/crowding and deep bite issues. Clear tray aligners are made from certified transparent polymeric (plastic) films and developed for patients based on a planning program prepared and implemented by an orthodontist or General Practitioner dentist. The plan entails three key stages:

(1) Creating impressions of the patient’s teeth

(2) Generating computer models for the production of desired profiles of the patient’s teeth

(3) Producing models of the patient’s teeth to be deployed in an incremental fashion.

Digital dentistry now makes the implementation of clear aligners into dental work-flow a lot simpler. Each of the key steps mentioned above can be handled using computer aided tools. The benefits of such an approach in dental practice are immense. Patient-specific treatment programs are developed by the dentist resulting in the custom-fabrication of the clear aligners for the patient. They are made from materials which do not irritate the skin and gums and also allow an easy removal from the mouth to perform other tasks such as teeth brushing and flossing. The diagram below outlines the work-flow which supports the application of clear aligners in orthodontic treatment.

3D printing technologies can be used to manufacture the impressions of the teeth then applied as a form in a thermoforming process to fabricate the clear tray aligners. This approach is cost saving and delivers the dimensional requirements for dental application. Through our expertise in the area of 3D Printing we will assist you in transferring the application of this tool to other aspects of your dental practice such as in muster development to aid consultations with patients.

3D Printed PEEK For Medical Practice

Author: Prof.Dr. Brando Okolo

3D Printing technologies bring with it the promise of replicating, in physical terms, digital designs and constructions in a straight forward fashion. The digital data may result from a construction effort using computer aided design tools or may be information acquired from imaging tools such as Magnetic Resonance Imaging scanner, Computer Tomography scanner or X-ray radiography device. Raw data from these scanning devices are conveniently converted to 3D Printer machine readable format (typically .stl) then printed as actual models of the organ or bio-component. With such possibilities in view it goes without saying that 3D Printing technologies can render new applications in medical practice.

Customization is one of the leveraging attributes of 3D Printing tools. In the medical practice such tools can support the industry’s drive to advance individualized patient care making it possible to develop treatment plans that are truly patient-specific, enhance the communication pathway amongst medical practitioners and build the confidence needed for success in treatment. Other key advantages of incorporating 3D Printing technologies in medical practice are that (i) the costs incurred from trials and bio-medical research can be reduced (ii) it becomes possible to fabricate parts which have geometric complexities that pose technical challenges for conventional manufacturing methods (iii) the deployment of customized medical products such as prosthetics and implants based on user-specific measurements will help reduce the trauma level in treated patients.

In the planning of surgical procedures, physicians and their teams rely on the 2-dimensional data of organs or human body structures provided from MRI, CT or radiography scans in order to make decisions critical for a successful operation. Working with 3-dimensional replica (1:1 scale) of such structure(s) can greatly improve and enhance the preparation process. The medical procedure can be simulated well in advance of the actual intervention allowing the medical team gain better insight to the patient’s specific case in a more profound way.

Indmatec GmbH has successfully demonstrated the feasibility of 3D printing high quality bio-medical structures from polyethertherketone (PEEK) material using the fused filament fabrication (FFF) technology. The input data for the printed parts were taken from MRI and CT scans of real human anatomy. Our technology and PEEK material are highly affordable compared to market conditions and exceed the quality expectations of end-users.