普-蠕双级时效对7050合金组织与性能的影响  

Effect of Two-stage Ordinary-creep Aging on Structure and Properties of 7050 Aluminum Alloy

作　　者：孟宪伟 康人木 曾舟 谢东 刘国标 李艳丽 MENG Xianwei;KANG Renmu;ZENG Zhou;XIE Dong;LIU Guobiao;LI Yanli(Sichuan Polytechnic University,Sichuan Deyang 618000,China;Deyang Products Quality Supervision and Inspection Institute,Sichuan Deyang 618000,China)

机构地区：[1]四川工程职业技术大学,四川德阳618000 [2]德阳市产品质量监督检验所,四川德阳618000

出　　处：《精密成形工程》2024年第8期121-129,共9页Journal of Netshape Forming Engineering

基　　金：四川省市场监督管理局科技计划(SCSJS2022021);四川工程职业技术学院规划科研项目(KJGH2020-16);德阳市科技计划(2023SZZ150)。

摘　　要：目的研究不同双级时效工艺对7050铝合金强度、硬度及耐腐蚀性能等的影响。方法通过金相组织观察、SEM分析、晶间腐蚀分析等方法,对比研究普通双级时效和普-蠕变双级时效处理后合金力学性能及抗腐蚀性能的变化。结果当一级时效温度为75℃时,普通双级时效和普-蠕变双级时效的抗拉强度达到最大值,分别为578.77MPa与548.08MPa。在相同腐蚀条件下,普通双级时效合金样品中出现了较明显的剥落腐蚀以及鼓泡起皮现象,程度略有差异,当一级时效温度为50℃和140℃时,试样表面分层严重,腐蚀坑深入到试样深处,出现明显爆皮。当一级时效温度为50℃和140℃时,普-蠕时效试样中出现了鼓泡与局部分层、轻微爆皮现象。结论随着一级时效温度的升高,2种方式时效的7050合金硬度、抗拉强度、抗腐蚀性能均先升高后降低,与普通双级时效相比,普-蠕变双级时效的7050铝合金抗拉强度略有降低,抗腐蚀性能显著提升。The work aims to study the effects of different two-stage aging processes on the comprehensive properties of 7050 aluminum alloy for aviation,such as strength,hardness and corrosion resistance.Metallographic observation,SEM analy-sis,intergranular corrosion analysis and other methods were used to study the mechanical properties and corrosion resistance of the alloys treated by two-stage ordinary aging and two-stage ordinary-creep aging;At the first stage aging temperature of 75℃,the tensile strength of two-stage ordinary aging and two-stage ordinary-creep aging reached its maximum value,which was 578.77 MPa and 548.08 MPa,respectively.Under the same corrosion conditions,two-stage ordinary aging alloy samples showed significant peeling corrosion,with slight differences in the degree of blistering and peeling.The surface of the samples aged at 50℃and 140℃had severe delamination,and the corrosion pits penetrated deep into the sample,resulting in obvious peeling.At the first stage aging temperature of 50℃and 140℃,the ordinary-creep aging sample showed bubbling and partial layering,as well as slight skin cracking.With the increase of the first stage aging temperature,the hardness,tensile strength and corrosion resistance of 7050 alloy aged by two methods first increases and then decreases.Compared with two-stage ordinary aging,the tensile strength of 7050 aluminum alloy under two-stage ordinary-creep aging decreases slightly,and the corrosion re-sistance is improved significantly.

关 键 词：普通双级时效 普-蠕双级时效 7050合金 力学性能 晶间腐蚀 剥落腐蚀 

分 类 号：TG166.3[金属学及工艺—热处理] TG146.21[金属学及工艺—金属学]