Additive Manufacturing of Carbides and their composites

TheCarbides are renowned for their mechanical strength, hardness and thermal stability. There is increasing industrial interest for small, complex parts of silicon carbide (SiC) and boron carbide (B4C) for aerospace, transportation and other applications. However, traditional forming processes require expensive moulds and struggle to produce these complex geometries. Additive manufacturing (AM) offers a promising alternative however, it struggles with carbides due to their high melting points and their optical properties. The overall aim of the project is to produce small, dense, complex parts of silicon carbide, boron carbide and their composites. To begin with the three techniques being investigated are robotic assisted deposition (or robocasting), diode area melting (DAM) and digital light processing (DLP). Robocasting is a continuous extrusion technique using pseudoplastic inks. The technique will be used to investigate reaction bonded SiC as well as SiC matrices with SiC fibres. On the other hand, DAM densifies a powder bed through laser absorption and reduced graphene oxide is being explored as a potential additive to increase the absorption of ceramic powders. Finally, DLP is a mask-based derivative of stereolithography. Photosensitive suspensions will be developed, and the mechanical properties of printed parts will be tested to try to develop a successful printing process.