冷拉拔过程中含稀土铝镁合金的组织与力学性能演变  

Microstructure and Mechanical Property Evolution of Rare Earth-Containing Al-Mg Alloy During Cold Drawing

作　　者：张欣[1] 杨光恒 王泽华[1] 周泽华[1] 易于[1] 蔡新[1] ZHANG Xin;YANG Guangheng;WANG Zehua;ZHOU Zehua;YI Yu;CAI Xin(College of Mechanics and Materials,Hohai University,Nanjing 211100,China)

机构地区：[1]河海大学力学与材料学院,南京211100

出　　处：《机械工程材料》2021年第10期34-42,共9页Materials For Mechanical Engineering

基　　金：国家自然科学基金资助项目(51909071);江苏省自然科学基金资助项目(BK20190493)。

摘　　要：熔炼制备不同稀土加入量的Al-3.0Mg-xRE(质量分数/%,x=0,0.12,0.31,RE为La+Ce)合金,研究了该合金的显微组织、硬度和拉伸性能在冷拉拔过程中的演变规律。结果表明:冷拉拔过程中,试验合金的晶粒拉长,第二相拉长并破碎成细小粒子,并在晶界和枝晶界处逐渐聚集呈线状分布,Copper{112}〈111〉型变形织构强度逐渐增高;随着变形量的增大,合金的强度呈线性增大,塑性降低,显微硬度增大;适量稀土(0.12%)的加入能够改善合金组织与力学性能,但过量稀土(0.31%)的加入会导致合金中第二相数量和尺寸的增加,从而降低合金的力学性能。冷拉拔后,Al-3.0Mg-0.12RE合金中第二相的长度最小,数量最少,变形织构强度最高,力学性能最优。Al-3.0 Mg-xRE(mass fraction/%,x=0,0.12,0.31,RE=La+Ce)alloys containing different-content rare earth were smelted.The evolution of the microstructure,hardness and tensile properties of the alloys were investigated in cold drawing.The results show that during the cold drawing,the grains of the test alloys were elongated;the second phase particles were also elongated and fragmented to small particles,and then gradually aligned on grain boundaries and dendrite boundaries in linearity;the intensity of Copper{112}〈111〉deforming texture increased.With increasing deformation amount,the strength of the alloys increased linearly,the plasticity decreased and the hardness increased.Proper rare earth addition(0.12%)could improve the microstructure and the mechanical properties of the alloy.However,excessive rare earth addition(0.31%)increased the number and size of the second phases in the alloy,thereby reducing the mechanical properties of the alloy.After cold drawing,the Al-3.0 Mg-0.12 RE alloy had the smallest and the least second phases,the highest deforming texture intensity and the best mechanical properties.

关 键 词：冷拉拔 铝镁合金 显微组织 力学性能 

分 类 号：TG174.442[金属学及工艺—金属表面处理]