放电等离子烧结工艺对ZrB_2-YAG陶瓷力学性能的影响

EFFCT OF SPARK PLASMA SINTERING TECHNOLOGY ON THE MECHANICAL PROPERTY OF ZrB_2-YAG CERAMICS

ZrB2具有优良的物理特性和化学稳定性而应用于许多领域,但是ZrB2难以烧结致密和在高温条件下容易被氧化。为了充分发挥ZrB2的优点,改善ZrB2的缺点,本文采用共沉淀法制备壳核式Al2O3-Y2O3/ZrB2复合粉体,通过放电等离子烧结法制备高致密的ZrB2-YAG陶瓷。研究结果表明:烧结温度由1300℃到1700℃时,陶瓷杨氏模量和断裂韧性都增大;在20MPa前,陶瓷杨氏模量和断裂韧性随着烧结压力增大而逐渐增大;在保温时间小于4min,陶瓷的杨氏模量和断裂韧性随着保温时间的延长而增大。

Because ZrB2 has some excellent physical performance and chemical stability,it has been widely applied in a lot of fields,but ZrB2 is too difficult to be densified during sintering and easy to be oxidized at high temperature.To keep advantages and improve disadvantages of ZrB2,A12O3-Y2O3/ZrB2 composite powders with shell-core structure are prepared by co-precipitation,and then high density ZrB2-YAG ceramics are prepared by spark plasma sintering.Young＇s modulus and fracture toughness of ZrB2-YAG ceramics are increased by increasing sintering temperature from 1300℃ to 1700℃.When the sintering pressure is less than 20MPa,Young＇s modulus and fracture toughness of ZrB2-YAG ceramics are gradually increased by increasing the sintering pressure.When the holding time is less than 4 min,Young＇s modulus and fracture toughness of ZrB2-YAG ceramics are gradually increased by increasing the holding time.