摘要
采用光学显微镜、洛氏硬度仪、万能材料试验机和导电率测试仪等研究了时效处理对7022铝合金力学性能和导电率的影响。结果表明:经过470℃固溶处理420 min后的合金的显微硬度为71.3 HRB,导电率为28.0%IACS,抗拉强度为525.5 MPa,伸长率为11.25%;时效处理过程中,合金的显微硬度、抗拉强度和导电率随着时效时间的增加呈现先升高后降低的变化趋势,而伸长率则与它们呈相反的变化趋势。150℃时效14 h后合金的硬度和导电率分别为89.5 HRB和31.2%IACS,110℃时效10 h后抗拉强度达到峰值,为607.85 MPa。综合考虑7022合金的导电率与力学性能,其最佳热处理制度为470℃固溶420 min+150℃时效14 h,此时合金的硬度值为89.5 HRB,导电率为31.2%IACS,抗拉强度为595.73 MPa,合金力学性能和导电率的变化为时效时间和时效温度综合作用的结果。
Effect of aging treatment on mechanical properties and electrical conductivity of 7022 aluminum alloy was studied by means of optical microscope,Rockwell hardness tester,universal material testing machine and conductivity tester.The results show that after solution treatment at 470℃for 420 min,the microhardness,electrical conductivity,tensile strength and elongation of the alloy are 71.3 HRB,28.0%IACS,525.5 MPa and 11.25%,respectively.During the aging treatment,the microhardness,tensile strength and electrical conductivity of the alloy first increase and then decrease with the increase of aging time,while the elongation first decreases and then increases.After aging at 150℃for 14 h,the hardness and conductivity of the alloy are 89.5 HRB and 31.2%IACS,respectively,and the tensile strength reaches the peak value of 607.85 MPa after aging at 110℃for 10 h.Considering the electrical conductivity and mechanical properties of the 7022 alloy,the optimal heat treatment process is solution treatment at 470℃for 420 min and aging at 150℃for 14 h,in which the hardness of the alloy is 89.5 HRB,the electrical conductivity is 31.2%IACS,and the tensile strength is 595.73 MPa.The changes of mechanical properties and electrical conductivity of the alloy are the combined effects of aging time and aging temperature.
作者
黎诚
殷剑
金康
LI Cheng;YIN Jian;JIN Kang(China Machinery Industry Technology Research Institute of Precision Forming,Wuhu 241000,China;Beijing Research Institute of Mechanical&Electrical Technology Ltd,Beijing 100083,China)
出处
《材料热处理学报》
CAS
CSCD
北大核心
2021年第12期61-68,共8页
Transactions of Materials and Heat Treatment
关键词
7022铝合金
时效热处理
导电率
微观组织
力学性能
7022 aluminum alloy
aging heat treatment
electrical conductivity
microstructure
mechanical property
