常压烧结制备亚微米晶Al_2O_3陶瓷及其力学性能研究  

Preparation and Mechanical Properties of Pressureless Sintered Al_2O_3 Ceramics with Submicrometer Grains

作　　者：张志林[1] 伍尚华[1] 游洋[1] 

机构地区：[1]广东工业大学机电工程学院,广州510006

出　　处：《材料导报》2014年第24期111-114,共4页Materials Reports

基　　金：广东省引进领军人才专项资金(400120001);广东省产学研结合项目(2009A090100015)

摘　　要：以高纯α-Al2O3粉体为原料,MgO-Y2O3为烧结助剂,采用常压烧结法制备亚微米晶Al2O3陶瓷。研究了烧结温度、烧结助剂对Al2O3陶瓷的致密化过程、显微结构及力学性能的影响。结果表明:添加一定量的复合助剂MgO-Y2O3可起到促进Al2O3陶瓷致密化,细化显微结构,并改善其力学性能的作用。经1450℃常压烧结1h可获得相对密度达99.6%、平均晶粒尺寸约0.71μm的亚微米晶Al2O3陶瓷,其维氏硬度和断裂韧性分别为18.5GPa和4.6 MPa·m1/2。Al2O3 ceramics with submicrometer grains were fabricated by pressureless sintering method,using high purity α-Al2O3 powders as starting material and MgO-Y2O3 as additive.The effects of sintering temperature and additive on densification process,microstructure and mechanical properties of Al2O3 were studied.The results show that the addition of MgO-Y2O3 additive could promote the densification,refine the microstructure and improve the mechanical properties of Al2O3.Submicrometer Al2O3 ceramics with relative density of 99.6 ％ and average grain size of about 0.71 μm can be obtained by sintering at 1450 ℃ for 1 h.The Vickers hardness and fracture toughness are 18.5 GPa and 4.6 MPa · m1/2,respectively.

关 键 词：AL2O3陶瓷 MgO-Y2O3 常压烧结 亚微米晶 

分 类 号：TB321[一般工业技术—材料科学与工程]