Mg-50Ti复合材料高温力学性能及显微组织研究  

Research on Elevated Temperature Mechanical Properties and Microstructure of Mg-50Ti Composite

作　　者：李实田 赵思聪[1,2] 马涛[1] 郭二军[1,2] 刘坤[1] 张道和 王雷[1,2] 冯义成[1,2] 刘东戎[1,2] LI Shi-tian;ZHAO Si-cong;MA Tao;GUO Er-jun;LIU Kun;ZHANG Dao-he;WANG Lei;FENG Yi-cheng;LIU Dong-rong(School of Materials Science and Chemical Engineering,Harbin University of Science and Technology,Harbin 150080,China;Key Laboratory of Advanced Manufacturing and Intelligent Technology(Ministry of Education),Harbin University of Science and Technology,Harbin 150080,China)

机构地区：[1]哈尔滨理工大学材料科学与化学工程学院,哈尔滨150080 [2]哈尔滨理工大学先进制造智能化技术教育部重点实验室,哈尔滨150080

出　　处：《哈尔滨理工大学学报》2022年第6期51-57,共7页Journal of Harbin University of Science and Technology

基　　金：国家自然科学基金(51804090,21801070,51971086);黑龙江省重点研发计划指导类项目(GZ20210080);黑龙江省普通本科高等学校青年创新人才培养计划(UNPYSCT-2020184);黑龙江省“百千万”工程科技重大专项(2019ZX10A01)。

摘　　要：采用粉末冶金法制备了具有良好高温力学性能的Mg-50Ti复合材料,利用拉伸试验机对复合材料的室温和高温性能进行测试,并运用光学显微镜和扫描电子显微镜对复合材料的显微组织及断口形貌进行观察。结果表明:Mg-50Ti复合材料在200℃拉伸时具有良好的高温力学性能,其抗拉强度仅较室温拉伸时下降5%,为97.6 MPa,断后伸长率为1.2%;随着拉伸测试温度的升高,复合材料的抗拉强度逐渐下降,断后伸长率逐渐提高,弹性模量逐渐下降。复合材料的断口表现为脆性断裂,断裂形式包括Mg基体断裂、增强体Ti颗粒断裂、增强体Ti颗粒与Mg基体界面脱粘,200℃以下拉伸断口主要表现为Mg基体断裂和增强体Ti颗粒断裂导致材料失效,而超过200℃的拉伸断裂形式逐渐转变为Mg基体断裂和增强体与基体的界面脱粘导致材料失效。Powder metallurgy was used to prepare Mg-50Ti composite with excellent elevated temperature mechanical properties.Tensile testing machine was used to test the room temperature and elevated temperature properties of the composite.The optical microscope and scanning electron microscope were used to analyze the microstructure and observe the fracture morphology.The results show that the Mg-50Ti composite achieved excellent elevated temperature mechanical properties at 200℃.Its ultimate tensile strength and elongation after fracture are 97.6 MPa and 1.2%,respectively.The tensile strength is only 5%lower than that at room temperature.As the tensile test temperature increased,the tensile strength of the composite gradually decreased,the elongation after fracture gradually increased,and the elastic modulus gradually decreased.The fracture surface of the composite under all tensile temperature is brittle fracture.The fracture mechanism includes Mg matrix cracking,reinforcement Ti particles fracture,Mg matrix and reinforcement Ti particles interface debonding.The failure fracture below 200℃is due to the fracture of the Mg matrix and Ti particles.While the fracture mechanism of the failure fracture over 200℃gradually transforms into the fracture of the Mg matrix,the debonding of the interface between the reinforcement and the matrix leads to the failure of the composite.

关 键 词：粉末冶金 Mg-50Ti复合材料 显微组织 高温拉伸 

分 类 号：TG146.2[一般工业技术—材料科学与工程]