Al2O3/ZrO2/MgAl2O4复相陶瓷的SPS烧结及性能表征  

Performance Characterization of Spark Plasma Sintered Al2O3/ZrO2/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 Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, Gansu, China;University of Chinese Academy of Sciences, Beijing 100049, China)

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

出　　处：《陶瓷学报》2019年第3期289-294,共6页Journal of Ceramics

基　　金：国家自然科学基金(91426301;11505247;11505246;11575258;11605256;U1832149)。

摘　　要：本文以Al2O3、3Y-ZrO2和MgO为原料,采用机械球磨法对粉末进行混合处理,通过放电等离子体烧结技术(SPS:Spark Plasma Sintering)制备了Al2O3/ZrO2/MgAl2O4(AZM)复相陶瓷,研究了MgAl2O4添加量对AZM复相陶瓷微观结构,力学、热学及电学性能的影响。X射线衍射分析表明复相陶瓷物相由α-Al2O3、t-ZrO2和MgAl2O4组成,无其余杂相。SEM断面形貌图显示复相陶瓷的断裂为沿晶断裂和穿晶断裂相结合的复合断裂模式。随MgAl2O4含量增加,复相陶瓷断裂韧性由12 MPa m1/2(MgAl 2O 4体积比: 0v.%)增加至17.48 MPa m 1/2(20v.%)后逐渐减小为14.46 MPa m 1/2(40v.%);维氏硬度由21 GPa(0v.%)逐渐降低至15.3 GPa(40v.%);同时,常温热导率由9.3 W/(m K)(20v.%)逐渐降低到7.6 W/(m K)(35v.%);热膨胀系数无明显变化。此外,200 ℃下AZM30(MgAl2O4体积比30v.%)和ZTA复相陶瓷电阻率分别为6.6 × 10^8 Ω cm和3.3 × 10^9 Ω cm。The α-Al2O3, ZrO2 and MgO powders were mixed by ball milling firstly, and then the Al2O3/ZrO2/MgAl2O4 (AZM) composite ceramics were prepared by spark plasma sintering (SPS). The effects of MgAl2O4 addition on microstructure, mechanical, thermal and electric properties of AZM composite ceramics were investigated. X-ray diffraction analysis indicated that the phases of the composite ceramics consisted of α-Al2O3, t-ZrO2 and MgAl2O4, without any other impurities. SEM cross-sectional images showed that the fracture mode of the AZM composite ceramics was a combination of intergranular fracture and transgranular fracture. With the increase of the MgAl2O4 content, the fracture toughness of composite ceramics increased from 12 MPa m1/2(0v.%) to 17.48 MPa m1/2(20v.%) at first and then decreased gradually to 14.46 MPa m1/2(40v.%), while the vickers hardness decreased gradually from 21 GPa(0 v.%) to 15.3 GPa(40v.%);meanwhile, the thermal conductivity decreased gradually from 9.3 W/(m K)(20v.%) to 7.6 W/(m K)(35v.%) at room temperature. However, MgAl2O4 has little impact on the coefficient of thermal expansion. Additionally, the electrical resistance of AZM30 and ZTA composite ceramics were 6.6 × 108 Ω cm(30v.%) and 3.3 × 109 Ω cm respectively at 200 ℃.

关 键 词：MGAL2O4 Al2O3/ZrO2 SPS 显微结构 物理性能 

分 类 号：TQ174.75[化学工程—陶瓷工业]