MgAl2O4掺杂对ZTA-MgAl2O4复相陶瓷力学及热学性能的影响  

Effect of MgAl2O4 Doping on Mechanical and Thermal Properties of ZTA-MgAl2O4 Composite Ceramics

作　　者：郭亚威 柴建龙 朱亚滨[1] 魏孔芳[1] 李淑芬 申铁龙[1] 姚存峰[1] 崔明焕[1] 王志光[1] GUO Yawei;CHAI Jianlong;ZHU Yabin;WEI Kongfang;LI Shufen;SHEN Tielong;YAO Cunfeng;CUI Minghuan;WANG Zhiguang(Institute of modem physics,Chinese academy of sciences,Lanzhou 730000,Gansu,China;University of Chinese academy of sciences,Beijing 10049,China)

机构地区：[1]中国科学院近代物理研究所,兰州730000 [2]中国科学院大学,北京100049

出　　处：《硅酸盐学报》2019年第12期1717-1722,共6页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金(11505247);中国科学院战略性先导专项项目(XDA21010202)资助

摘　　要：以Al2O3、ZrO2、MgO为初始粉末,采用放电等离子体烧结(SPS)制备ZTA-MgAl2O4复相陶瓷,研究MgAl2O4掺杂对ZTA-MgAl2O4复相陶瓷微观结构,力学及热学性能的影响。结果表明:ZTA-MgAl2O4复相陶瓷物相包括α-Al2O3、t-ZrO2和MgAl2O4,烧结过程中MgO与Al2O3完全反应生成MgAl2O4;随MgAl2O4添加量增加,复相陶瓷Vickers硬度由21 GPa逐渐降低至17.5 GPa;而断裂韧性及抗弯强度呈现先增大后减小的趋势,当MgAl2O4添加量为15%(体积分数)时,断裂韧性和弯曲强度达到最大值,分别为8.55 MPa·m^1/2和1056 MPa;此外,相同测试温度下复相陶瓷热导率随MgAl2O4添加量的增加逐渐减小,如温度为50℃时复相陶瓷热导率由18.5 W/(m·K)逐渐降低到14.3 W/(m·K)。ZTA-MgAl2O4 composite ceramics were prepared via spark plasma sintering(SPS)with Al2O3,ZrO2 and MgO as raw powders.The effect of MgAl2O4 doping on the microstructure,mechanical and thermal properties of ZTA-MgAl2O4 composite ceramics was investigated.The results show that the ZTA-MgAl2O4 composite ceramics consist of corundum(α-Al2O3),zirconia(ZrO2)and spine(MgAl2O4),indicating that MgO and Al2O3 react completely to form MgAl2O4 during sintering.The Vickers hardness gradually decreases from 21 to 15.31 GPa,while the fracture toughness and flexural strength of composite ceramics first increase and then decrease with the increase of MgAl2O4 content.The sample with MgAl2O4 content of 15%exhibits the maximum fracture toughness(i.e.,8.55 MPa·m^1/2)and flexural strength(i.e.,1056 GPa).The thermal conductivity of composite ceramics decreases with the increase of MgAl2O4 content at the same temperature.For instance,the thermal conductivity of composite ceramics decreases gradually from 18.5 to 14.3 W/(m·K)as MgAl2O4 content increases from 0 to 30%at 50℃.

关 键 词：镁铝尖晶石 氧化锆增韧氧化铝复相陶瓷 微观结构 力学性能 热学性能 

分 类 号：TQ174.75[化学工程—陶瓷工业]