晶粒向心取向织构化SiAlON陶瓷  

Textured SiAlON Ceramic with Centripetal Grain Alignment

作　　者：肖水清 谭大旺 李卫 郭伟明[2] 林华泰 XIAO Shuiqing;TAN Dawang;LI Wei;GUO Weiming;LIN Huatay(School of Electromechanical Engineering,Lingnan Normal University,Zhanjiang 524048,China;School of Electromechanical Engineering,Guangdong University of Technology,Guangzhou 510006,China)

机构地区：[1]岭南师范学院机电工程学院,广东湛江524048 [2]广东工业大学机电工程学院,广州510006

出　　处：《硅酸盐学报》2023年第12期3144-3151,共8页Journal of The Chinese Ceramic Society

基　　金：岭南师范学院校级人才引进专项项目(ZL2021006,ZL22024);国家自然科学基金(52172066)。

摘　　要：采用放电等离子快速加热,通过外径限制环压缩法进行烧结–锻造,获得了晶粒向心取向的织构化SiAlON陶瓷,并对其显微结构、织构化程度和力学性能各向异性特点进行了分析。结果表明,SiAlON陶瓷棒状晶粒c轴(长轴)高度平行于圆柱样品的直径方向,形成辐射状取向。在垂直加压方向和平行径向的截面,SiAlON陶瓷晶粒的c轴与径向夹角的平均值分布为19.2°和9.9°,向心取向织构化程度为0.79。在垂直加压方向截面的硬度比垂直径向截面的硬度高12%左右,达到17.85 GPa;抗弯强度在断裂面垂直径向时比断裂方向平行径向高57%左右,为1 341 MPa;断裂韧性在裂纹扩展垂直径向时比平行径向的高74%左右,为6.27 MPa·m^(1/2)。A textured SiAlON ceramic with a centripetal grain alignment was obtained via sinter-forging through outer diameter strain ring compression using spark plasma heating.The microstructure,texturing degree and anisotropy of mechanical properties of the ceramic were investigated.The results show that the c-axis(i.e.,long axis) of the rod-like SiAlON grains is parallel to the radial direction of the cylindrical sample,forming a centripetal grain alignment.The average included angle between the c-axis and radial direction is 19.2° and 9.9° on the plane perpendicular to pressing direction and parallel to radial direction,respectively.The degree of centripetal texture is 0.79.The hardness on the plane perpendicular to pressing direction is 12% greater than that on the plane perpendicular to radial section,reaching 17.85 GPa.The flexural strength with fracture plane perpendicular to radial section is 57%greater than that with fracture direction parallel to radial direction,which is 1 341 MPa.The fracture toughness with crack propagation perpendicular to radial section is 75% higher than that with crack direction parallel to radial direction,which is 6.27 MPa·m~(1/2).

关 键 词：SIALON 织构化 向心取向 各向异性 

分 类 号：TB321[一般工业技术—材料科学与工程]