冷轧对固溶时效Mg-Li合金显微组织及性能的影响  

Effect of Cold Rolling on Microstructure and Properties of Solution-aged Mg-Li Alloy

作　　者：刘旭贺 解海涛[2] 肖阳[2] 张红松[1] 

机构地区：[1]河南工程学院机械工程学院 [2]郑州轻金属研究院金属材料研究所

出　　处：《特种铸造及有色合金》2018年第1期21-24,共4页Special Casting & Nonferrous Alloys

基　　金：河南省高校科技创新团队项目(18IRTSTHN005);河南工程学院博士基金(D2017015);国家自然科学基金资助项目(51371161)

摘　　要：对固溶时效的Mg-11Li-3Al-xZr(x=0、0.1)合金挤压板进行了轧制,采用OM、XRD分析了轧制前后合金显微组织的变化,通过拉伸试验测试了不同变形量下合金的拉伸性能。结果表明,固溶时效合金组织主要由β-Li和少量颗粒状化合物组成,轧制过程中合金内部析出α-Mg、θ-MgLi_2Al以及AlLi等相,并且随着轧制进行,θ-MgLi_2Al相逐渐转变为AlLi相。随着轧制变形量增大,合金晶粒尺寸变大,固溶时效Mg-11Li-3Al-xZr合金的力学性能先升高后降低。Mg-11Li-3Al合金在60%冷变形量时综合性能最好(抗拉强度为242 MPa,伸长率为46%);Mg-11Li-3Al-0.1Zr合金在40%变形量下综合性能最佳(抗拉强度为255 MPa,伸长率为24%)。The solution treatment, aging and cold rolling were carried out the extruded Mg-11Li-3Al-~z＇Zr （~t-~0, 0.1 ,mass fractim, % ） alloys,and the microstructures and properties of the alloy before and after rolling were analyzed by OM, XRD and testing machine. The results show that the solution and aged MgqlLi-3Al-xZr alloy is mainly composed of fl-Li and a little granular compound, and α-Mg, θ-MgLi2 Al and AlIA phase can be precipitated during the rolling process, and then the θ-MgLi2 Al phase is gradually transformed into AlLi phase. With the increase of the rolling deformation rate, the grain size in the alloy is increased. The strength and elongation of the Mg-11Li-3Al-xZr alloy are increased at first and then decreased. Under proper deformation, both the strength and plasticity of the alloy can be improved because of the combination effects of solution strengthening, work hardening and the decomposition of strengthening phase and grain coarsening. Mg-11Li-3Al alloy has the best comprehensive performance at 60% cold deformation, where tensile strength and elongcotion reach 242 MPa and 46%. respectively, while Mg-11Li-3Al-0.1Zr alloy has the best comprehensive performance at 40% deformation, where tensile strength and elongation reach 255 MPa and 24%, respectively.

关 键 词：MG-LI合金 固溶时效 冷轧 显微组织 力学性能 

分 类 号：TG33[金属学及工艺—金属压力加工] TG146.21[一般工业技术—材料科学与工程]