| 摘要 |
PURPOSE:To improve bending strength, toughness, hardness, etc., by forming a specific alpha-sialon composition and sintering the formed compact in an inert gas. CONSTITUTION:An alpha-sialon composition, composed of Si3N4 with >=15wt.% beta-Si3N4 content, AlN and oxides of one or two or more metallic elements (M) selected from Li, Ca, Mg, Y and lanthanide elements (except La and Ce) and having the composition formula Mx(Si,Al)12(O,N)16 (x is 0<=x<=0.8), as necessary, is mixed with 0.5-40wt.% oxide, nitride, carbide or boride (e.g. SiO2) of a metal without forming a solid solution with the alpha-sialon in the presence of an organic solvent in a bowl or a container made of the alpha-sialon or a container made of a resin and then spray-dried to afford a molding raw material. The resultant raw material is subsequently formed, degreased, then heated and sintered at 1600-2000 deg.C to afford the objective alpha-sialon-based sintered compact having >=100kgf/mm<2> bending strength (JIS R-1601; three-point bending). |
