| 摘要 |
PURPOSE:To produce a pure silicon nitride sintered material having high strength in a simple apparatus, by charging a material to be sintered consisting of silicon nitride into a crucible whose surface is constituted by dense silicon carbide and burning the material under ordinary pressure while inhibiting the enter of the outer air. CONSTITUTION:A crucible wherein at least part of the surface is constituted by dense silicon carbide whose open porosity is preferably <=10vol.% is prepared. A material to be sintered consisting of silicon nitride is inserted into the crucible and burned under ordinary pressure while inhibiting the entry of the open air to provided the aimed silicon carbide sintered material. According to the above- mentioned method, the silicon nitride having high strength can be produced, since the silicon nitride unreacts with nitrogen and silicon produced by thermal decomposition of silicon nitride when burned and the partial pressure of nitrogen gas produced can be maintained to high state, because the crucible whose surface is constituted by dense silicon carbide is used. |
