无铅易切削铝-铜合金挤压棒材的热处理工艺研究  

Research on Heat Treatment Process of Extruded Lead-free Free Cutting Al-Cu Alloy Bar

作　　者：张大鹏 覃建波 牛艳萍 石常亮 周春荣 ZHANG Dapeng;QIN Jianbo;NIU Yanping;SHI Changliang;ZHOU Chunrong(Guangdong Lingsheng New Material Technology Co.,Ltd.,Foshan 528031,Guangdong China;Center of Industrial Analysis and Testing,Guangdong Academy of Sciences,Guangzhou 510650,Guangdong China;Guangdong Fine special profile Co.,Ltd.,Qingyuan 511533,Guangdong China)

机构地区：[1]广东领胜新材料科技有限公司,广东佛山528031 [2]广东省科学院工业分析检测中心,广东广州510650 [3]广东精美特种型材有限公司,广东清远511533

出　　处：《热处理》2021年第3期27-30,40,共5页Heat Treatment

摘　　要：对直径为40mm、含5.8%Cu、0.41%Bi、0.42%Sn、0.07%Si、0.08%Fe和0.04%Ti(质量分数)的无铅铝-铜合金挤压棒材进行了固溶和时效处理。固溶处理工艺分别为490℃、500℃、510℃和520℃保温2h水冷,时效温度分别为180℃、190℃和200℃,时效时间分别为2h、4h、6h、8h、10h和12h。采用光学显微镜、扫描电镜、拉伸试验和高速车削试验研究了棒材的显微组织、力学性能和切削性能。结果表明:固溶温度越高,棒材中粗大块状CuAl2相溶解越充分;在不同温度时效,随着时效时间的延长,棒材的抗拉强度先上升后下降,断后伸长率则先下降后上升。铝-铜合金挤压棒材的最佳热处理工艺为520℃×2h水冷固溶处理随后180℃×8h时效处理。经此工艺热处理的铝-铜合金挤压棒材抗拉强度为463.8MPa,断后伸长率为9.7%,且切屑易断、不缠绕刀具,切削性能良好。The extruded lead-free free cutting Al-Cu alloy bars 40 mm in diameter containing 5.8%Cu,0.41%Bi,0.42%Sn,0.07%Si,0.08%Fe and 0.04%Ti by mass were solution treated by heating at 490℃,500℃,510℃,and 520℃ for 2 h and water-cooling,respectively,and then aged at 180℃,190℃,and 200℃ for 2 h,4 h,6 h,8 h,10 h,and 12 h,respectively.Microstructure,mechanical properties and machinability of the bars were investigated by means of optical microscope,scanning electron microscope,tensile test and high-speed turning test.The results showed that the higher the solid solution temperature was,the more fully the coarse massive CuAl2 phase dissolved in the bar;and as time at different aging temperatures became longer,the tensile strength increased at first and then decreased,whereas the elongation decreased at first and then increased.The optimum heat treatment processes of the extruded Al-Cu alloy bar were as follows:solution treating which consisted of heating at 520℃ for 2 h and water-cooling,and then aging at 180℃ for 8 h.The extruded Al-Cu alloy bar heat treated by this means exhibited tensile strength of 463.8 MPa,elongation of 9.7%and good machinability that was embodied in the chips easy of breaking thus not winding cutter.

关 键 词：铝-铜合金 切削性能 挤压 固溶处理 时效 

分 类 号：TG166.3[金属学及工艺—热处理]