New 3D printing process creates strong, complex ceramic parts
HRL Laboratories' preceramic monomer build material eliminates porosity of traditional ceramic processing.
Typically, ceramic parts are formed by sintering powders but doing so introduces porosity, the researchers say, which limits both the complexity of the part shapes possible as well as the component’s ultimate strength. Although 3D printing allows for complex shapes not suited to casting or machining, ceramic powders also don’t bond similar to polymer or metal powder build materials.
To overcome these limitations, HRL’s Senior Chemical Engineer Zak Eckel and Senior Chemist Dr. Chaoyin Zhou invented a photo sensitive preceramic monomers that can be used in a stereo lithography 3D printer to form complex components. The parts are then kiln fired to convert them into a high strength, fully dense ceramic. According to the researchers, the resulting silicon oxycarbide ceramic parts can withstand temperatures in excess of 1700°C and are ten times stronger than ceramic foams of similar density.
“With our new 3D printing process we can take full advantage of the many desirable properties of this silicon oxycarbide ceramic, including high hardness, strength and temperature capability as well as resistance to abrasion and corrosion.” says program manager Dr. Tobias Schaedler.
According to the researchers, the process be valuable in a range of applications from large components in jet engines and hypersonic vehicles to intricate parts in microelectromechanical systems and electronic device packaging. The HRL team’s research paper, “Additive Manufacturing of Polymer Derived Ceramics,” was published in the January 1st issue of Science.