3D printing for medical applications

Additive manufacturing is an inherent part of industrial manufacturing. In the fields of prototyping, fabricating individual parts and complex geometries, or research and development can be found various procedures like 3D printing technologies, which enrich those fields.

Due to the various technologies, additive manufacturing is on the way to be utilized in the medicine sector.  Besides special designed medical tools, prostheses and implants are the most desired products for medical 3D printing. 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.

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. 

High-performance filament PEEK

High-performance filament PEEK

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 500 °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 P155, developed by Apium Additive Technologies GmbH. Till now the printer is only designed for industrial applications.  

Apium P155 - High-performance polymer 3D printer

Apium P155 - High-performance polymer 3D printer

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

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 P155 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 the use in 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 to 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/.

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. Impeller system 3D printed from PEEK, housing is 3D printed from polyamide (PA6).

Figure 4. Impeller 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. 

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.

INDMATEC GMBH MACHT PEEK FILAMENT FÜR DIE HERSTELLUNG VON MEDIZINPRODUKTEN VERFÜGBAR

PEEK ist ein Hochleistungskunststoff, der im letzten Frühjahr vom Karlsruher Startup Indmatec als Filament für FDM©/FFF-3D-Drucker auf den Markt gebracht wurde. Seine Verwendbarkeit für die Herstellung von Medizinprodukten bis zur Klasse IIa wurde jetzt mit einer erfolgreichen biologischen Qualifizierung nach EN ISO 10993-5/-4/-18 bestätigt.


Das ab Februar 2016 erhältliche “PEEK MedTec“ Filament ist einsetzbar für verschiedene medizinische, dentale und chirurgische Anwendungen. Zudem lässt sich das Filament im Prototyping für medizinische Produkte wie Prothesen verwenden. Dank der Kombination aus dem Hochleistungspolymer für medizinische Zwecke und der 3D-Druck-Methode „Fused Filament Fabrication“ (FFF) können geometrisch anspruchsvolle und aufwendige Objekte, wie Sekundärkronen, Gerüste, spezielle chirurgische Werkzeuge sowie Bauteile für Endoskope jetzt kostengünstig, schnell und unkompliziert hergestellt werden.

PEEK (Polyetherehterketon) selbst wird schon seit längerer Zeit im medizinischen sowie zahnmedizinischen Sektor verwendet. Gründe für die besondere Eignung sind sein geringes Gewicht und eine hohe Abriebfestigkeit. PEEK ist zudem "knochenverträglicher" als herkömmliche Metallimplantate. Bei diagnostischen Untersuchungen wie Röntgen erweist es sich als wenig störend und muss in der Regel nicht umständlich entfernt werden. Die PEEK-Implantate werden derzeit noch mit traditionellen, kostenintensiven und zeitraubenden Fertigungsverfahren hergestellt. Mit der anvisierten Zertifizierung des Materials als Medizinprodukt für den 3D-Druck können PEEK-Teile in naher Zukunft in jedem Krankenhaus und Dentallabor schnell und wirtschaftlich gefertigt werden – eine gute Nachricht für Patienten, Krankenkassen, Ärzte und das gesamte Gesundheitssystem.

Passend zum PEEK-Filament präsentierte Indmatec im August vergangenen Jahres bereits die 2. Generation seines speziell für Hochleistungspolymere entwickelten FFF 3D-Druckers, den „HPP 155“. Nach der Zulassung des PEEK Filaments wird Indmatec in Kürze auch den FFF 3D-Drucker HPP 155 in einer speziellen Variante für den medizinischen Gebrauch auf den Markt bringen.

„Neben PEEK im „technical grade“ kann der HPP 155 auch weitere Hochleistungsfilamente, die wir für die Industrie entwickeln, drucken. Dazu zählt unter anderem PVDF (Polyvinylidene Fluoride)", berichtet Tony Tran-Mai, einer der Gründer und Geschäftsführer des Karlsruher Unternehmens, nicht ganz ohne Stolz, von den Alleinstellungsmerkmalen des neuen 3D-Druckers. „Denn PEEK als Filament für den 3D-Drucker eignet sich längst nicht nur für medizinische Aufgabenstellungen.“ 

Nachdem es Indmatec im vergangenen Jahr gelungen war, PEEK mit dem FFF Verfahren 3D-druckfähig zu machen, und den passenden FFF-3D-Drucker zu bauen, zeigen sich auch viele andere Industriebereiche hoch interessiert. Die Vorteile liegen auf der Hand: Das PEEK-Filament zeichnet sich nicht nur durch zahlreiche positive Eigenschaften wie hohe mechanische Steifigkeit und Abriebfestigkeit, sondern auch durch hohe chemische Beständigkeit aus. Ein besonderer Vorteil, der dieses Polymer gegenüber allen anderen FFF-Materialien so einzigartig und begehrenswert macht, ist seine Temperaturbeständigkeit. Sein Schmelzpunkt liegt bei 343°C. Aufgrund der metallähnlichen Eigenschaften und seiner Eignung für Bauteile in Leichtbauweise sind die PEEK-3D-Druck Lösungen von Indmatec optimal einsetzbar für industrielle Zwecke. 

MÖGLICHE ANWENDUNGEN

Download als PDF - Pressemitteilung

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.