Sumihiko Kurita

Development of self-hardening slip casting

Abstract The self-hardening slip casting ‘NK-Process’ has been developed. It becomes possible to form near-net shapes and thick bodies of advanced ceramics, etc., with excellent properties when sintered. Y-PSZ slip containing a small quantity (3 wt%) of epoxy resin and hardener, was self-hardened at room temperature to 70 °C. The increase of the slip viscosity depended on the curing temperature, and the time for hardening could be shortened to 10 min at 70 °C. The three-point bending strength of sintered Y-PSZ increased up to 1300 MPa. This process can be applied to various advanced ceramics, such as Y-PSZ, alumina, and silicon nitride. In particular, we have succeeded in forming ceramics turbo rotor and gas turbine rotor made of silicon nitride.