免热处理(TiB_(2)+ZrB_(2))/Al-Mg-Mn基复合材料的显微组织与力学性能  

Microstructure and enhanced mechanical properties of(TiB_(2)+ZrB_(2))/Al-Mg-Mn composite with no heat treatment

作　　者：罗钧毅 姜云[1] 林波[1] LUO Jun-yi;JIANG Yun;LIN Bo(School of Mechanical Engineering,Guizhou University,Guiyang 550025,China)

机构地区：[1]贵州大学机械工程学院,贵阳550025

出　　处：《中国有色金属学报》2023年第10期3195-3204,共10页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(52265043);贵州省科技计划资助项目(ZK2021[054]);贵州省科技计划资助项目(ZK2021[267]);贵州省科技成果应用与产业化项目(2021[067]);贵州大学培育项目(2019[23])。

摘　　要：基于交通、航空航天等领域高强韧精密复杂零件免热处理的需求,采用原位生成反应法制备了(TiB_(2)+ZrB_(2))/Al-Mg-Mn基复合材料,对比研究了重力铸造和挤压铸造制备的(TiB_(2)+ZrB_(2))/Al-Mg-Mn基复合材料的微观组织和力学性能。结果表明:原位生成反应法制备的复合材料中生成了大量纳米级的TiB_(2)和ZrB_(2)颗粒。拉伸实验结果表明,挤压铸造复合材料试样的抗拉强度、屈服强度和伸长率分别为296 MPa、185 MPa和12.2%,这些参数比重力铸造成型的Al-Mg-Mn合金分别提高了57%、95%和40%;比重力铸造复合材料分别提高了12%、11%和36%。分析发现,复合材料相比无添加Al-Mg-Mn合金强韧性能更高的原因在于TiB_(2)和ZrB_(2)颗粒协同增强细晶强化作用;而挤压铸造成型的复合材料的力学性能优于重力铸造成型的复合材料的主要原因在于挤压力所致的晶粒细化和Orowan强化作用。(TiB_(2)+ZrB_(2))/Al-Mg-Mn matrix composites were prepared by in-situ reaction synthesis based on the requirement of free of heat treatment in transportation,aerospace and other fields for precision complex structural parts with high strength and toughness.The microstructure and mechanical properties of the composites produced by gravity casting and squeeze casting were studied.The results show that a large number of nano-sized TiB_(2)and ZrB_(2)particles are generated in the composites during the in-situ reaction synthesis process.The tensile test results show that the ultimate tensile strength(UTS),the yield strength(YS)and the elongation(EL)of the squeeze casting composite are 296 MPa,185 MPa and 12.2%,respectively.These values are 57%,95%and 40%higher than those of gravity casting Al-Mg-Mn alloy,and are 12%,11%and 36%higher than those of gravity casting composite,respectively.It is found that the strength and toughness of the composite higher than that of Al-Mg-Mn alloy can be attributed to the synergistic strengthening effect of TiB_(2)and ZrB_(2)particles,and the reason of mechanical properties of squeeze casting composites better than those of gravity casting composites is due to the grain refinement and Orowan strengthening caused by squeeze pressure.

关 键 词：双相增强颗粒 铝基复合材料 免热处理 挤压铸造 原位反应合成 

分 类 号：TB333[一般工业技术—材料科学与工程]