氧化铝陶瓷柱状晶组织的形成及性能

摘要

This paper studies the microscopic morphology and properties of alumina ceramics by introdu-cing CAS and MgO. The result indicates that an addition of 0. 6% CAS additive inα-Al2 O3 changes the crystal growth kinetics conditions,which prompts the growth of rod-like alumina grain with a maximal 8:1 length-diameter ratio and an obvious improvement in density and fracture toughness. The joint use of 0. 8% CAS and 0. 1% MgO additives can further improve the sintered body density to a maximal figure of 97. 4% while keeping the growth of rod-like grain.%通过加入 CAS（CaO - Al2 O3- SiO2）和 MgO 两种添加剂，对氧化铝陶瓷柱状晶的形成和性能进行了研究.结果表明，在α- Al2 O3粉体中加入0.6wt％ CAS 添加剂，可以改变氧化铝陶瓷晶体的生长动力学条件，促使晶粒择优在某个方向上生长成柱状晶，长径比最大可达到8：1，氧化铝陶瓷的密度和断裂韧性都有明显提高.当0.8wt％CAS 联合0.1wt％ MgO 使用时，在促进柱状晶生长的同时，能够进一步提高氧化铝陶瓷的致密度，使相对密度最大值达到97.4％.