预时效处理对Al-Zn-Mg-Cu合金硬化响应及微观组织的影响  

Effect of pre-aging treatment on hardening response and microstructure of Al-Zn-Mg-Cu alloy

作　　者：魏茂源[1,2] 王洪真 张红 滕敦波[1,2] Wei Maoyuan;Wang Hongzhen;Zhang Hong;Teng Dunbo(College of Engineering,Yantai Nanshan University,Yantai Shandong 265700,China;National Engineering Research Center for Plastic Working of Aluminum Alloys,Shandong Nanshan Aluminum Co.,Ltd.,Yantai Shandong 265713,China)

机构地区：[1]烟台南山学院工学院,山东烟台265700 [2]山东南山铝业股份有限公司国家铝合金压力加工工程技术研究中心,山东烟台265713

出　　处：《金属热处理》2020年第7期90-93,共4页Heat Treatment of Metals

基　　金：山东省高校科技计划(J18KA028);龙口市科技计划(2017GG23)。

摘　　要：研究了预时效处理对Al-Zn-Mg-Cu铝合金薄板力学性能和微观组织的影响,测试了显微硬度和力学性能,表征了TEM微观精细组织。结果表明:固溶处理后在180℃立即进行人工时效处理,可获得Al-Zn-Mg-Cu合金的显著时效硬化效果,且在8 h后达到峰值硬度195 HV0.5,与基体呈共格关系的η'相为主要强化相;120℃×10 min为最佳的预时效处理制度,经14天的室温停滞后,相比于固溶+自然时效态,硬度降低了13 HV0.5,降幅达到10.7%,具有明显的抑制自然时效作用;预时效+自然时效态试样,经烘烤硬化处理后,屈服强度和抗拉强度分别达到了465和545 MPa,强度增量分别达到170和95 MPa,同时伸长率达到12.5%。Effect of pre-aging treatment on mechanical properties and microstructure of Al-Zn-Mg-Cu aluminum alloy was investigated.The micro-hardness and mechanical properties were tested.The microstructure was characterized.The results indicate that the best pre-aging hardening effect of the experimental Al-Zn-Mg-Cu aluminum alloy is achieved while aging at 180℃immediately after solution treatment,during which the peak value reaches 195 HV0.5 and the main hardening phase isη'phase.The optimal pre-aging treatment is under 120℃×10 min.Thus,after 14 days natural aging,the hardness of the alloy is decreased by 13 HV0.5 or 10.7%compared to the solution+natural aging treatment.Finally after bake hardening process,the yield strength and tensile strength of the pre-aged alloy reach 465 MPa and 545 MPa,showing a hardening increase of 170 MPa and 95 MPa,respectively,and the elongation reaches 12.5%.

关 键 词：AL-ZN-MG-CU铝合金 力学性能 预时效处理 微观组织 

分 类 号：TG156.1[金属学及工艺—热处理]