李芳,牛天昊,王雨,徐戊矫

• 1:重庆大学材料科学与工程学院

摘要(Abstract)：

采用光学显微镜、扫描电镜、透射电镜、室温拉伸实验和晶间腐蚀实验等研究了固溶处理时间对7050铝合金挤压棒材力学性能及耐腐蚀性能的影响。结果表明:挤压后未热处理的7050铝合金的强度和耐腐蚀性能都比较差,其抗拉强度为564.2 MPa,腐蚀最大深度达到50.83μm。经过固溶+T6时效后,7050铝合金在再结晶软化与沉淀强化的共同作用下,其抗拉强度先增加后降低;经470℃固溶处理30 min+T6时效后,7050铝合金抗拉强度达到最高值674 MPa,耐腐蚀性能最好。随着固溶时间从30 min增加至2 h,峰值时效后的合金的晶界类型由弯曲小角度晶界变为平直大角度晶界,晶界处从无第二相析出状态转变为有间断分布的棒状η相状态,η相附近形成无沉淀析出带。在晶界类型转变、η相和无沉淀析出带共同作用下,7050铝合金的耐腐蚀性能变差。

关键词(KeyWords)： 7050铝合金;固溶时间;力学性能;晶间腐蚀

Abstract:

Keywords:

基金项目(Foundation):

作者(Author): 李芳,牛天昊,王雨,徐戊矫

DOI: 10.13289/j.issn.1009-6264.2021-0060

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