AIN-ZrO_2(PSZ)系の加圧焼結(<小特集>セラミック材料小特集)

概要

論文の詳細を見る
Powder mixtures of AlN and ZrO_2(PSZ), in which the amounts of ZrO_2 content were 6〜70 mol%, were hot-pressed at 1200〜2000℃ for 30 minutes under a pressure of 20 MPa in reducing atmosphere. When the amount of ZrO_2 in the powder mixture was 33 mol% (ZrO_2/AlN=1/2), all raw powders of AlN and ZrO_2 completely reacted, giving a good sintered composite material with brilliant golden colour and finely dispersed reacted products of AlON Spinel, α-Al_2O_3 and ZrN. For the systems above 33 mol% ZrO_2, excess ZrO_2 (cubic phase) remained as an unreacted material, while below 33 mol% ZrO_2 unreacted AlN remained. In the case of the ratio of ZrO_2/AlN=1/2, a good sintered composite material was obtained and its bending strength σ_f, toughness K_<Ic>, Vickers hardness H_V and Youngs modulus E were 448 MPa, 2.72 MN/m^<3/2>, 15.3 GPa, and 354 GPa, respectively. ZrN, one of the reaction products, was oxidized by the heat-treatment at 750℃ in air and changed to ZrO_2. This oxdation reaction of ZrN to ZrO_2 gave volume expansion of abut 27%. The effect of the surface compressive stress and microcracks arising from this volume expansion on the mechanical properties of the sintered body were discussed.
社団法人日本材料学会の論文
1984-11-15