基于粉末床技术放电等离子烧结Si3N4陶瓷圆柱体  

Fabrication of cylindrical Si_(3)N_(4) ceramics by spark plasma sintering based on the powder bed technology

作　　者：蔡培彬 顾乾坤 郭伟明[1] 罗嗣春 林华泰 CAI Peibin;GU Qiankun;GUO Weiming;LUO Sichun;LIN Huatai(School of Electromechanical Engineering,Guangdong University of Technology,Guangzhou 510006,China;School of Mechanical and Electronic Engineering,Pingxiang University,Pingxiang 337055,China)

机构地区：[1]广东工业大学机电工程学院,广州510006 [2]萍乡学院机械电子工程学院,萍乡337055

出　　处：《粉末冶金材料科学与工程》2023年第2期113-119,共7页Materials Science and Engineering of Powder Metallurgy

基　　金：国家自然科学基金资助项目(52172066)。

摘　　要：将平均粒径分别为150μm和50μm的SiC粉体与平均粒径分别为150μm和50μm的石墨粉体混合,得到粗粉末床(150μm SiC+150μm石墨)与细粉末床(50μm SiC+50μm石墨),粉末床中SiC与石墨的体积分数均为50%。采用粉末床技术对圆柱形Si_(3)N_(4)陶瓷预烧体进行放电等离子烧结,研究粗、细粉末床、预烧温度(1400℃和1500℃)和粉末床回收对等离子烧结Si_(3)N_(4)陶瓷圆柱体的变形程度、致密度、物相组成和显微结构的影响。结果表明,采用粗粒径粉末床、1500℃预烧温度和回收使用一次的粉末床制备的Si_(3)N_(4)陶瓷圆柱体,横截面形状保持度最高,达到93%,维氏硬度和断裂韧性分别为(18.73±0.24)GPa和(3.64±0.23)MPa·m^(1/2)。Si_(3)N_(4)陶瓷的主相为α-Si_(3)N_(4),晶粒形貌为等轴状。通过引入粉末床可克服放电等离子烧结制备Si_(3)N_(4)陶瓷制品的形状限制,有望实现高性能异形Si_(3)N_(4)陶瓷的制备。SiC powders with average particle sizes of 150μm and 50μm were mixed with graphite powders with average particle sizes of 150μm and 50μm respectively to obtain coarse particle size powder bed(150μm SiC+150μm graphite)and fine particle size(50μm SiC+50μm graphite);the volume fractions of SiC and graphite in the powder bed were both 50%.Pre-sintered cylindrical Si_(3)N_(4)green body was sintered by spark plasma sintering(SPS)based on powder bed technology.The effects of two different particle size bed powders,pre-sintering temperature(1400℃and 1500℃)and powder bed recovery on the deformation degree,density,phase composition and microstructure of cylindrical Si_(3)N_(4)ceramics were investigated.The research results show that the circular section retention of cylindrical Si_(3)N_(4)ceramic prepared by combining the coarse particle size powder bed,a pre-sintering temperature of 1500℃and a recycled once powder bed is the best,reaching 93%;the Vickers hardness and fracture toughness are(18.73±0.24)GPa and(3.64±0.23)MPa·m^(1/2),respectively.Due to the low sintering temperature(1500℃),the main phase of the as-sintered ceramics isα-Si_(3)N_(4);the grain morphology is equiaxed.This study shows that the shape limitation of the Si_(3)N_(4)ceramics prepared by SPS can be overcame by introducing the powder bed.This technology is expected to realize the preparation of high-performance Si_(3)N_(4)ceramics with complex shapes.

关 键 词：异形Si_(3)N_(4)陶瓷 粉末床 放电等离子烧结 圆形截面保持度 力学性能 

分 类 号：TB321[一般工业技术—材料科学与工程]