| 摘要 |
PURPOSE:To enhance toughness of the stokes by utilizing slurry having specified viscosity and producing the stokes so that an SiC whisker is orientated and dispersed in an Si3N4 matrix nearly parallel to the wall surface of the stokes two-dimensionally at random. CONSTITUTION:Slurry having <=3.0 poise viscosity is obtained by mixing Si3N4 having about 1mum particle diameter, 5-30wt.% SiC whisker having about 0.1-1mum diameter and about 5-100mum length and about 15wt.% cordierite-based sintering adjuvant with water added with a dispersant. This slurry is introduced into a gypsum mold to obtain a green molded body having >=60% density. This is roasted at about 1700 deg.C for about 3 hours in the N2 atmosphere. Thereby the tough stokes having large relative density is obtained wherein the SiC whisker 1 is orientated and dispersed in the Si3N4 matrix 3 nearly parallel to both the outer surface 2 of the stokes and the wall face of the inner surface 2' two- dimensionally at random. Furthermore tensile stress imparted on the outer surface is reduced and the progress of the generated fine cracks 4, 4' is stopped. |
