3D-Printed Composites for High Temperature Uses
materials and coatings
3D-Printed Composites for High Temperature Uses (LEW-TOPS-145)
Using Laser Sintering to Manufacture Thermoset Polyimide Composites
Overview
Innovators at the NASA Glenn Research Center, in collaboration with the University of Louisville and the U.S. Air Force, have developed an additive manufacturing technique to produce composite parts with high-temperature capabilities using thermoset polyimide resins. The process uses selective laser sintering (SLS) to melt-process a powdered version of NASA's novel RTM370 imide resin filled with finely milled carbon fibers. The resulting composite part can be subsequently post-cured to prepare for high temperature aerospace applications, offering a 3D-printed composite part that can withstand temperatures over 300 °C. This is a significant advancement in the state-of-the-art in additive manufacturing polymers, offering an SLS process that requires relatively low melting temperatures and creates composites with high temperature capabilities, enabling 3D-printing of parts with complex geometry for high performance applications.
The Technology
NASA's technology is the first successful 3D-printing of high temperature carbon fiber filled thermoset polyimide composites. Selective Laser Sintering (SLS) of carbon-filled RTM370 is followed by post-curing to achieve higher temperature capability, resulting in a composite part with a glass transition temperature of 370 °C.
SLS typically uses thermoplastic polymeric powders and the resultant parts have a useful temperature range of 150-185 °C, while often being weaker compared to traditionally processed materials. Recently, higher temperature thermoplastics have been manufactured into 3D parts by high temperature SLS that requires a melting temperature of 380 °C, but the usable temperature range for these parts is still under 200 °C.
NASA's thermoset polyimide composites are melt-processable between 150-240 °C, allowing the use of regular SLS machines. The resultant parts are subsequently post-cured using multi-step cycles that slowly heat the material to slightly below its glass transition temperature, while avoiding dimensional change during the process. This invention will greatly benefit aerospace companies in the production of parts with complex geometry for engine components requiring over 300 °C applications, while having a wealth of other potential applications including, but not limited to, printing legacy parts for military aircraft and producing components for high performance electric cars.


Benefits
- High-temperature capability: NASA's thermoset polyimide composites retain mechanical properties at extremely high temperatures (over 300 °C)
- Simple production of high-performance, complex 3D parts: Objects with complicated structures that require high temperature applications can be 3D-printed by a regular SLS machine
- Lightweight components: Parts made from RTM370 composites are 30 percent lighter than metallic parts
- Clean and green: RTM370 uses a solvent-free production process that does not produce any harmful, volatile compounds
- Excellent impact-resistance and char yield: RTM370 composites demonstrate high impact resistance and outstanding abrasion resistance at ambient and high temperatures
Applications
- Aerospace
- Automotive
- Commercial space
- Construction
- Electronics
- Industrial machinery
- Marine
- Mechanical systems
- Oil and gas
Technology Details
materials and coatings
LEW-TOPS-145
LEW-19873-1
LEW-17618-1
"Laser Sintering of Thermoset Polyimide Composites," Kathy C. Chuang, et al., September 23, 2019,
https://ntrs.nasa.gov/search.jsp?R=20190031841.
https://ntrs.nasa.gov/search.jsp?R=20190031841.
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