La_(2)O_(3)和Al_(2)O_(3)对α-SiAlON陶瓷显微结构和性能的影响  

Effect of La_(2)O_(3)and Al_(2)O_(3)on Microstructure and Properties of α-SiAlON Ceramics

作　　者：张晶 孙峰 张伟儒 徐学敏[1] 王梅 ZHANG Jing;SUN Feng;ZHANG Weiru;XU Xuemin;WANG Mei(Sinoma Advanced Nitride Ceramics Co.,Ltd.,Zibo 255000,Shandong,China;Shandong Industrial Ceramic Research&Design Institute Co.,Ltd.,Zibo 255000,Shandong,China)

机构地区：[1]中材高新氮化物陶瓷有限公司,山东淄博255000 [2]山东工业陶瓷研究设计院有限公司,山东淄博255000

出　　处：《陶瓷学报》2022年第6期1015-1022,共8页Journal of Ceramics

基　　金：国家重点研发计划(2020YFB0407701)。

摘　　要：以α-Si_(3)N_(4)为原料,采用两步气压烧结在相对较低的温度下成功制备出自增韧α-SiAlON陶瓷,研究了La_(2)O_(3)和Al_(2)O_(3)对α-SiAlON陶瓷致密化、显微结构及力学性能的影响。结果表明,随着La_(2)O_(3)比例的升高,样品的相对密度、抗弯强度和维氏硬度均降低,断裂韧性则先升高后降低。当nY∶nLa比例为9∶1时,随着Al_(2)O_(3)加入量的增加,样品的相对密度、抗弯强度和断裂韧性升高,维氏硬度逐渐降低。当Al_(2)O_(3)加入量为3 wt.%时,样品的上述性能分别为99.7%、(1202±43)MPa、(8.0±0.3)MPa·m^(1/2)和(17.5±0.2)GPa。当同时加入La_(2)O_(3)和Al_(2)O_(3)时,虽然降低了α-SiAlON相含量,但促进了α-SiAlON和β-SiAlON晶粒的各向异性生长,获得了兼具高强、高硬、高韧特性的SiAlON陶瓷。In-situ toughenedα-SiAlON ceramics were successfully prepared by using two-step gas pressure sintering at relatively low temperature withα-Si_(3)N_(4) powder as raw material.The effects of La_(2)O_(3)and Al_(2)O_(3)on the densification,microstructure and mechanical properties ofα-SiAlON ceramics were studied.With increasing proportion of La_(2)O_(3),relative density,flexural strength and Vickers hardness of the samples decreased,while fracture toughness increased firstly and then decreased.When nY:nLa was equal to 9:1,with increasing content of Al_(2)O_(3),relative density,flexural strength and fracture toughness of the samples increased,while the Vickers hardness decreased gradually.The above properties of the samples with 3 wt.%Al_(2)O_(3)were 99.7%,(1202±43)MPa,(8.0±0.3)MPa·m^(1/2),and(17.5±0.2)GPa,respectively.SiAlON ceramics with high strength,high hardness and high toughness can be obtained with simultaneous addition of La_(2)O_(3)and Al_(2)O_(3)due to the acceleration of the anisotropic growth ofα-andβ-SiAlON grains,despite the decrease in the phase content ofα-SiAlON.

关 键 词：Α-SIALON 自增韧 显微结构 力学性能 La_(2)O_(3) 

分 类 号：TQ174.75[化学工程—陶瓷工业]