预拉伸对2A14铝合金显微组织、力学性能和腐蚀性能的影响  

Effects of pre-stretch on microstructure,mechanical properties and corrosion resistance of 2A14 aluminum alloy

作　　者：黄兰萍 何龙龙[1,3] 李松 刘文胜 黄静[1,3] 陈送义[4,5] Lan-ping HUANG;Long-long HE;Song LI;Wen-sheng LIU;Jing HUANG;Song-yi CHEN(Powder Metallurgy Research Institute,Central South University,Changsha 410083,China;State Key Laboratory of Light Weight and High Strength Structural Materials,Central South University,Changsha 410083,China;State Key Laboratory of Powder Metallurgy,Central South University,Changsha 410083,China;Light Alloy Research Institute,Central South University,Changsha 410083,China;Collaborative Innovation Center of Advance Nonferrous Structural Materials and Manufacturing,Central South University,Changsha 410083,China)

机构地区：[1]中南大学粉末冶金研究院,长沙410083 [2]中南大学轻质高强结构材料国家级重点实验室,长沙410083 [3]中南大学粉末冶金国家重点实验室,长沙410083 [4]中南大学轻合金研究院,长沙410083 [5]中南大学有色金属先进结构材料与制造协同创新中心,长沙410083

出　　处：《Transactions of Nonferrous Metals Society of China》2024年第4期1065-1080,共16页中国有色金属学报（英文版）

基　　金：primarily financially supported by the National Natural Science Foundation of China(No.51871245);the National Key R&D Program of China(No.2017YFE0301505);State Key Laboratory for Powder Metallurgy as well as State Key Laboratory of Light Weight and High Strength Structural Materials,Central South University,China。

摘　　要：研究预拉伸变形量对峰值时效态2A14铝合金显微组织、力学性能和腐蚀行为的影响。结果表明:由于预拉伸导致细小弥散的θ′相在基体中大量析出,合金的硬度和强度都明显提升;在峰值时效前引入预拉伸可以明显提高峰值时效硬度并加快到达峰值时效时间;当预拉伸变形量为7.5%时,θ′相的分布明显变得更不均匀,这导致极限抗拉强度的下降;随着预拉伸变形量增加,合金塑性、冲击韧性和剥落腐蚀抗力均逐渐下降,但晶间腐蚀抗力先提高后下降。The microstructure,mechanical properties and corrosion behaviors of the peak-aged 2A14 aluminum alloys subjected to pre-stretch prior to artificial aging were investigated.The results indicate that the hardness and strength of the peak-aged alloy can be greatly enhanced via introducing pre-stretch due to the formation of dense and finerθ′precipitates with dispersed distribution in alloy matrix.Pre-stretch prior to peak aging evidently enhances the peak aging hardness and shortens the peak aging time of the alloy.A pre-stretching degree of 7.5%leads to a distinct inhomogeneous distribution ofθ′phase,which decreases the ultimate tensile strength.As pre-stretching degree increases,the plasticity,impact toughness and exfoliation corrosion(EXCO)resistance of the peak-aged alloy all gradually decrease,but its resistance to intergranular corrosion(IGC)increases and then decreases.

关 键 词：2A14铝合金 预拉伸 显微组织 力学性能 腐蚀抗力 

分 类 号：TG146.21[一般工业技术—材料科学与工程]