烧结温度对氮化硅层状陶瓷材料微观组织和力学性能的影响  

Effects of Sintering Temperature on Microstructure and Mechanical Properties of Silicon Nitride Layered Ceramics

作　　者：刘家宝 宋金鹏 高姣姣[2] 胡士恒 孟维其 王瑶 LIU Jiabao;SONG Jinpeng;GAO Jiaojiao;HU Shiheng;MENG Weiqi;WANG Yao(Shanxi Key Laboratory of Procision Machining,College of Mechanical and Vehicle Engineering,Taiyuan University of Technology,Taiyuan 030024,China;College of Aeronautics and Astronautics,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]太原理工大学机械与运载工程学院精密加工山西省重点实验室,山西太原030024 [2]太原理工大学航空航天学院,山西太原030024

出　　处：《热加工工艺》2024年第5期84-90,共7页Hot Working Technology

基　　金：国家自然科学基金资助项目(51875388,52205492);山西省高等学校科技创新项目(2021L067)。

摘　　要：采用交替铺层技术成功制备了以α-Si_(3)N_(4)为基体,Y_(2)O_(3)-MgO-WC和GdF_(3)-MgO分别作为A层和B层添加相的层状素坯。采用真空热压烧结技术,分别以烧结温度为1550、1600、1650、1700、1750℃,压力为30 MPa,保温时间为60 min,制备了Si_(3)N_(4)-Y_(2)O_(3)-MgO-WC/Si_(3)N_(4)-GdF_(3)-MgO层状陶瓷材料,并研究了烧结温度对氮化硅层状陶瓷材料微观组织和力学性能的影响。结果表明:氮化硅层状陶瓷材料的断裂韧度随着温度的升高先增后减,最高断裂韧度出现在烧结温度为1650℃时,其中面断裂韧度为7.844 MPa·m^(1/2),层断裂韧度为7.294 MPa·m^(1/2)。同时,层状陶瓷材料的抗弯强度和硬度随烧结温度升高先减后增。当烧结温度为1550℃时,抗弯强度为841.797 MPa,面维氏硬度为16.227 GPa。此外,层状陶瓷材料的断裂方式为穿晶断裂和沿晶断裂的混合模式。The alternate layering technique was used to successfully prepare a layered powder billet withα-Si_(3)N_(4) as the matrix,Y_(2)O_(3)-MgO-WC and GdF_(3)-MgO as the additive phase of A layer and B layer,respectively.Using vacuum hot pressing sintering technology,the sintering temperature of 1550,1600,1650,1700,1750℃,the pressure was 30 MPa,the holding time was 60 min,the silicon nitride layered ceramic material was prepared.The effects of sintering temperature on the microstructure and mechanical properties of silicon nitride layered ceramics were studied.The results show that the fracture toughness of layered ceramic materials increases first and then decreases with the increase of sintering temperature.When the sintering temperature is 1650℃,the fracture toughness is the highest,the midplane fracture toughness is 7.844 MPa·m^(1/2),and the layer fracture toughness is 7.294 MPa·m^(1/2).At the same time,with the increase of sintering temperature,the flexural strength and hardness of laminated ceramic materials first decrease and then increase.When the sintering temperature is 1550℃,the flexural strength is 841.797 MPa,the surface Vickers hardness is 16.227 GPa.In addition,the fracture mode of layered ceramic materials is a hybrid mode of transgranular fracture and intergranular fracture.

关 键 词：氮化硅层状陶瓷 烧结温度 微观组织 力学性能 

分 类 号：TB33[一般工业技术—材料科学与工程]