烧结工艺对涂覆法制备Y-Ce-La-TZP陶瓷微观结构与力学性能的影响  

Effects of sintering process on microstructures and mechanical properties of Y-Ce-La-TZP ceramics prepared by coating method

作　　者：吴飞 刘允中[1] 朱康乐 WU Fei;LIU Yunzhong;ZHU Kangle(National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials,South China University of Technology,Guangzhou 510640,China)

机构地区：[1]华南理工大学国家金属材料近净成形工程技术研究中心,广州510640

出　　处：《粉末冶金材料科学与工程》2021年第3期202-210,共9页Materials Science and Engineering of Powder Metallurgy

基　　金：广东省科技计划资助项目(2016A020220005)。

摘　　要：采用新型涂覆法,将Y(NO_(3))_(3)、Ce(NO_(3))_(3)和La(NO_(3))_(3)混合溶液涂覆于ZrO_(2)表面,制备多元稀土共掺杂的ZrO_(2)陶瓷粉体,再通过无压烧结制备1.5Y-5.5Ce-0.3La-TZP(摩尔分数,%)块体材料,研究烧结温度、保温时间和升温速率对ZrO_(2)陶瓷相对密度、显气孔率、线收缩率、相变转化、力学性能以及显微组织的影响。结果表明:随烧结温度升高,单斜相ZrO_(2)含量减少,当烧结温度为1550℃时,单斜相含量几乎为0,四方相的稳定化程度达到最大;在1200~1450℃烧结温度下,降低升温速率有利于陶瓷的烧结致密化。在1550℃保温90 min的ZrO_(2)陶瓷的相对密度、抗弯强度、硬度(HV_(10))以及断裂韧性均达到最大,分别为98.8%、1001.3 MPa、1124.3和10.81 MPa·m^(1/2)。Zirconia powders Co-doped with multiple rare earths were prepared by coating Y(NO_(3))_(3),Ce(NO_(3))_(3) and La(NO_(3))_(3) on the surface of ZrO_(2) by a novel coating method,and then 1.5Y-5.5Ce-0.3La-TZP tetragonal zirconia bulk materials were prepared by pressureless sintering.The effects of sintering temperature,holding time and heating rate on the relative density,apparent porosity,linear shrinkage,phase transformation,mechanical properties and microstructures of zirconia ceramics were studied.The results show that the content of monoclinic phase decreases with the increase of sintering temperature.When the sintering temperature is 1550℃,the content of monoclinic phase is almost zero,and the degree of tetragonal phase stabilization reaches the maximum.At the sintering temperature of 1200-1450℃,decreasing the heating rate is beneficial to the densification of ceramics.The relative density,bending strength,hardness(HV_(10))and fracture toughness of ZrO_(2) ceramics reach the maximum at 1550℃for 90 min,which are 98.8%,1001.3 MPa,1124.3 and 10.81 MPa·m^(1/2),respectively.

关 键 词：氧化锆陶瓷 烧结温度 保温时间 升温速度 微观组织 力学性能 

分 类 号：TQ174.75[化学工程—陶瓷工业]