预时效温度对AA7075铝合金烘烤硬化响应的影响  

Effect of pre-aging temperature on bake hardening response of AA7075 aluminum alloy

作　　者：张凯杰 姜壹夫 施金汭 杨峰 Zhang Kaijie;Jiang Yifu;Shi Jinrui;Yang Feng(School of Mechanical Engineering,Shenyang Institute of Engineering,Shenyang Liaoning 110136,China;The Key Laboratory of Reliability and Health Management of Energy and Power Equipment in Liaoning Province,Shenyang Liaoning 110136,China)

机构地区：[1]沈阳工程学院机械学院,辽宁沈阳1110136 [2]辽宁省能源电力装备可靠性与健康管理重点实验室,辽宁沈阳110136

出　　处：《金属热处理》2024年第12期90-93,共4页Heat Treatment of Metals

基　　金：沈阳工程学院大学生创新创业训练计划(D202404132013170531)。

摘　　要：采用(高分辨)透射电镜、显微硬度计以及拉伸试验机,研究了180℃×30 min烘烤前120~180℃×5 min预时效对AA7075高强铝合金烘烤硬化响应的影响。结果表明,当预时效前的预应变为3%~30%时,预应变的增大也会促使烘烤硬化效果更加明显。当预应变为5%时,随着预时效温度的升高(120~180℃),AA7075合金的η′强化相逐渐增多,强度和硬度分别从405 MPa和142 HV5升至478 MPa和160 HV5。同时,当预时效处理为180℃×5 min时,基体存在一定量的η′相和少量的η相,在烘烤前添加预时效工艺可显著促进GP区的形成,烘烤硬化响应最好。Effect of pre-aging at 120-180℃for 5 min before baking at 180℃for 30 min on the bake hardening response of AA7075 high-strength aluminum alloy was studied using high-resolution transmission electron microscopy,microhardness tester,and tensile testing machine.The results indicate that when the pre-strain before pre-aging is 3%-30%,an increase in the pre-strain will also promote a more significant bake hardening effect.When the pre-strain is 5%,with the increase of pre-aging temperature(120-180℃),theη′strengthening phase amount of the AA7075 alloy gradually increases,and the strength and hardness increase from 405 MPa and 142 HV5 to 478 MPa and 160 HV5,respectively.At the same time,when pre-aged at 180℃for 5 min,there is a certain amount ofη′phase and a small amount ofηphase in the matrix.Adding pre-aging process before baking enables to promote the formation of GP zone significantly,and the bake hardening response is the best.

关 键 词：AA7075铝合金 烘烤硬化响应 微观组织 拉伸性能 

分 类 号：TG166.3[金属学及工艺—热处理]