Design, Construction and Performance of Silicon Nitride Tool Parts in Steel Thixoforming
The design and performance of silicon nitride (Si3N4) dies for the semi-solid processing of steels is studied by the example of a punch and a lower swage in upset forging. The observed failure mechanisms and degradation effects are related to short-term effects resulting from mechanical and thermal loads and long-term effects owing to chemical and tribological attack. Results show that well-defined process conditions (cycle time, solidification time in the die) and a ceramic-suitable design are a pre-requisite for reliability and sufficient service life of ceramic dies.
C.G. Kang, S.K. Kim and S.Y. Lee
R. Telle et al., "Design, Construction and Performance of Silicon Nitride Tool Parts in Steel Thixoforming", Solid State Phenomena, Vols. 116-117, pp. 690-695, 2006