单级时效对Al-Mg-Si-Cu合金拉伸及晶间腐蚀性能的影响  

Effects of Single-stage Aging on Tensile Properties and Intergranular Corrosion of Al-Mg-Si-Cu Alloy

作　　者：李海 田奎生[1] 王芝秀 LI Hai;TIAN Kuisheng;WANG Zhixiu(School of Materials Science and Engineering,Changzhou University,Changzhou 213164,China;Jiangsu Key Laboratory of Materials Surface Science and Technology,Changzhou University,Changzhou 213164,China)

机构地区：[1]常州大学材料科学与工程学院,江苏常州213164 [2]常州大学江苏省材料表面科学与技术重点实验室,江苏常州213164

出　　处：《热加工工艺》2023年第16期111-114,共4页Hot Working Technology

基　　金：国家自然科学基金资助项目(51571038,51671038);江苏省高等学校自然科学研究重大项目(18KJA430002)。

摘　　要：为了寻求强度与耐蚀性良好配合,采用拉伸测试和加速腐蚀实验,研究了180~210℃/1~10 h单级时效对Al-Mg-Si-Cu合金拉伸性能和晶间腐蚀敏感性的影响。结果表明,随着时效时间延长,合金强度先升高后降低,伸长率则逐渐下降,晶间腐蚀深度先增大后减小,腐蚀类型由晶间腐蚀转变为均匀腐蚀;提高时效温度,合金硬化及软化速度均加快。经200℃/6 h单级时效,合金不仅无晶间腐蚀敏感性,还有较高的拉伸性能,抗拉强度、屈服强度和伸长率分别为374、359 MPa和9.9%。透射电镜观察表明,200℃/6 h单级时效合金基体析出相为均匀分布的Q’和β’相,晶界析出相呈球状、断续分布,这种析出特征赋予了合金高的强度和晶间腐蚀抗力。To achieve good combination of strength and corrosion resistance,the tensile test and accelerated corrosion test were used to study the effect of single-stage aging at 180-210℃for 110 h on the tensile properties and intergranular corrosion sensitivity of an Al-Mg-Si-Cu alloys.The results show that with the increase of aging time,the alloy strength firstly increases and then decreases,the elongation decreases gradually,the intergranular corrosion depth imcreases first and then decreases,and the corrosion mode changes from intergranular corrosion to uniform corrosion.With increase of the aging temperature,the hardening and softening rate of the alloy increases gradually.After 200℃/6 h single-stage aging,the alloy not only has no intergranular corrision sensitivity,but also has high tensile properties,the tensile strength,the yield strength and elongation of alloy are 374 MPa,359 MPa and 9.9%respectively,accompanied by uniform corrosion.Transmission electron microscopy observations show that the matrix precipitates of the alloy for single aged at 200℃for 6 h are Q'andβ'phases and grain boundary precipitates are spherical and discontinuously distributed.This precipitation characteristic gives the alloy high strength and intergranular corrosion resistance.

关 键 词：AL-MG-SI-CU合金 时效 力学性能 晶间腐蚀 

分 类 号：TG166.3[金属学及工艺—热处理]