导线用高强度高导电性铜-铬合金的热处理和性能研究  

Heat Treating and Properties of High-strength and High-conductivity Copper-chromium Alloy for Wire

作　　者：石军 刘伟 吴建辉 SHI Jun;LIU Wei;WU Jianhui(State Grid Henan Electric Power Company, Shangqiu Henan 476000, China)

机构地区：[1]国网河南省电力公司,河南商丘476000

出　　处：《上海金属》2020年第3期32-38,共7页Shanghai Metals

基　　金：国网河南省电力公司科技项目(No.5217B01800NZ);国家自然科学基金(No.51164015)。

摘　　要：高强度高导电性铜-铬合金是一种接触导线用铜合金,含0.79%Cr、0.11%Zr、0.06%La和0.06%Y(质量分数)。研究了铸态、固溶态、时效态和冷轧后时效态铜-铬合金的显微组织、硬度和导电性能。固溶处理工艺为950℃×60 min水冷,时效温度为400~600℃,时效时间0~360 mm,冷轧变形量20%~80%。结果表明:铸态铜-铬合金的组织为黑色Cr相和含钇和镧的亮白色Cu5Zr相;固溶处理后Cu5Zr相基本回溶于基体,黑色Cr相细小弥散;经60%冷轧变形的合金晶粒沿轧制方向拉长,尺寸约为400μm;时效时间相同,随着时效温度的升高,合金的硬度和电导率均提高;与未经冷轧的时效态铜-铬合金相比,经冷轧变形并时效的合金达到最高电导率的时效时间较短,且冷轧变形60%随后500℃时效60 min的合金硬度明显高于未经冷轧、500℃时效360 min的合金;冷轧变形60%、500℃时效60 min的铜-铬合金中有高密度位错和位错缠结,弥散的纳米级第二相与基体保持共格关系,使合金强化。High-strength and high-conductivity copper-chromium alloy containing 0.79%Cr,0.11%Zr,0.06%La and 0.06%Y by mass is a copper alloy for contact wire.Microstructure,hardness and conductivity of the copper-chromium alloy in cast,solution treated,aged,and cold-rolled then aged conditions were investigated.The solution treatment process was soaking at 950℃for 60 min and water-cooling,the aging temperature was ranging from 400℃to 600℃,and the aging time was varying from 0 to 360 min,the deformation amounts of cold-rolling were from 20%to 80%.The results showed that:(a)as-cast microstructure of the alloy was comprised of black Cr-phase and bright-white Cu5Zr phase containing yttrium and lanthanum;(b)after solution treating Cu5Zr phase was largely dissolved back into the matrix,and the black Cr-phase became relatively fine and dispersed;(c)the alloy exhibited grains as size as 400μm elongated in the rolling direction;(d)as aging temperature increased,so too did both the hardness and conductivity of the alloy aged at different temperatures for the same time;(e)the alloy cold rolled and aged for shorter time offered maximum conductivity as compared with the alloy not cold rolled but aged,and the alloy cold rolled to deformation amount of 60%then aged at 500℃for 60 min gave obviously higher hardness than the alloy not cold rolled but aged at 500℃for 360 min;(f)high density dislocations and dislocation entanglement formed in the alloy cold rolled to deformation amount of 60%and aged at 500℃for 60 min,and dispersed nano-sized second phases had a coherent relation to the matrix,being able to strengthen the alloy.

关 键 词：铜-铬合金 热处理 冷变形 组织 性能 

分 类 号：TG1[金属学及工艺—金属学]