退火对冷轧的高纯Al-4% Cu合金微观组织和性能的影响  

Effect of Annealing on Microstructures and Properties of Highly Pure Al-4%Cu Alloy

作　　者：周伟[1,2] 张凌峰 熊毅[1,2] 刘玉亮 任凤章[1,2] ZHOU Wei;ZHANGLingfeng;XIONG Yi;LIUYuliang;REN Fengzhang(School of Materials Science and Engineering,Henan University of Science and Technology,Luoyang 471023,Henan China;Collaborative Innovation Center of Nonferrous Metals Henan Province,Luoyang 471023,Henan China)

机构地区：[1]河南科技大学材料科学与工程学院,河南洛阳471023 [2]有色金属共性技术河南省协同创新中心,河南洛阳471023

出　　处：《热处理》2018年第3期6-11,共6页Heat Treatment

基　　金：河南省高等学校重点科研项目(17A430017);河南科技大学创新能力培育基金(2014ZCX007)

摘　　要：将尺寸为φ140 mm×130 mm作为靶材的高纯Al-4%Cu合金铸锭锻造、固溶处理及压下量为80%冷轧后,分别在150℃、200℃、250℃和300℃保温30 min退火。通过拉伸试验、硬度测定、X射线衍射和透射电镜研究了退火温度对合金显微组织和力学性能的影响。结果表明:在200℃退火的合金中有少量Al_2Cu相析出;在250℃退火后,合金中析出大量针状纳米级θ'(Al_2Cu)相,并弥散分布于基体中,显著提高了靶材的抗冲击性能;在300℃退火的合金中第二相明显粗化,其尺寸约为1μm,易导致冲击过程中靶材微裂纹的产生。此外,退火后,合金的抗拉强度从冷轧态的369 MPa降低到了173 MPa,而断后伸长率则从3.5%升高到了15.6%,这说明高纯Al-4%Cu合金的第二相析出强化效果明显受到了加工硬化效果由于退火而消除的影响。Highly pure Al-4% Cu alloy ingot 140 mm in diameter by 130 mm long, used as a target, was successively forged, solution treated, cold rolled to a reduction of 80%, and annealed at 150 ℃, 200 ℃,250 ℃,and 300℃ for 30 min, respectively. The effect of the annealing temperatures on microstructures and mechanical properties of the alloy was investigated by means of tensile test, hardness test, X-ray diffraction and transmission electron microscope. The results showed that a small amount of Al2 Cu phase was precipitated in the alloy annealed at 200 ℃, and that a large amount of needle-like nano-scale θ’ phase（Al2 Cu） was precipitated and dispersed in the alloy annealed at 250 ℃, rendering impact resistance of target much better, and second phase in the alloy annealed at 300 ℃ coarsened to as size as about 1 μm, being easy to result in creation of micro-crack in target during impact. Moreover, tensile strength of the alloy decreased from 369 MPa in the cold-rolled state to 173 MPa in the annealed state, whereas its elongation increased from 3.5% in the cold-rolled state to 15. 6% in the annealed state, which indicated that removal of work-hardening effect as a result of the annealing exerted considerable influence on precipitation strengthening effect of the second phase for the highly pure Al-4%Cu alloy.

关 键 词：高纯铝-铜合金 第二相 弥散强化 位错密度 

分 类 号：TG146.21[一般工业技术—材料科学与工程]