时效处理对Cu-Ni-Si合金应力松弛行为影响研究  

Efffects of Aging Processs on Stress Relaxation Behavior of Cu-Ni-Si Alloy

作　　者：杨耀鹏 张彦敏[1] 王要利[1] 刘爱奎 冯江[1] 张朝民 宋克兴[1,3] Yang Yaopeng;Zhang Yanmin;Wang Yaoli;Liu Aikui;Feng Jiang;Zhang Chaomin;Song Kexing(School of Materials Science and Engineering,Henan University of Science and Technology;KMD Precise Copper Strap(Henan)Co.,Ltd.;Henan Academy of Sciences)

机构地区：[1]河南科技大学材料科学与工程学院,河南洛阳471000 [2]凯美龙精密铜板带(河南)有限公司 [3]河南省科学院

出　　处：《特种铸造及有色合金》2023年第9期1230-1234,共5页Special Casting & Nonferrous Alloys

基　　金：河南省重大科技专项基金资助项目(221100210300);河南省科学院科研开发专项基金资助项目(220910009)。

摘　　要：对Cu-Ni-Si合金带材进行400~550℃、0.25~8 h的时效处理,根据时效后带材的力学性能,选择合适的时效处理工艺。对原始态与时效后带材进行125℃、初始加载应力为80%的屈服强度下的48 h应力松弛试验。结果表明,随着时效温度升高和时间延长,合金屈服强度均有所下降,经450℃×1 h时效后带材屈服强度为571 MPa,与原始态接近;应力松弛试验后,原始态合金剩余应力为391 MPa,应力松弛率为10.82%;时效态剩余应力为390 MPa,应力松弛率为8.85%,时效后的抗应力松弛性能提升了18.21%。对比分析原始态与时效态合金的微观组织发现,时效后析出相的数量增多且弥散分布,平均尺寸由67 nm减小到35 nm;孪晶规律分布且宽度尺寸减小,平均宽度由551 nm减小到126 nm;位错密度降低会进一步减少位错运动,这是Cu-Ni-Si合金带材的抗应力松弛性能提升的主要原因。The aging treatment at 400~550℃for 0.25~8 h was carried out on Cu-Ni-Si copper alloy strip,and appropriate aging treatment process was adopted according to the mechanical properties of aged strip.The stress relaxation experiment was conducted on primary and aged stripe at 125℃for 48 h with yield strength of 80%.The results indicate that with increase of aging temperature and time,the yield strength is decreased,which is 571 MPa after 450℃×1 h treatment,approaching the primary one.After the stress relaxation experiment,the residual stress and stress relaxation rate of primary strip reach up to 391 MPa and 10.82%,and those of the aged ones is 390 MPa and 8.85%,respectively,where the stress relaxation resistance is increased by 18.21%after aging treatment.Compared with the primary ones,the quantities of precipitated phase are increased and dispersed after aging treatment,of which the average size is reduced from 67 nm to 35 nm.The twins are distributed regularly with width reduction,where the average width size is decreased from 551 nm to 126 nm,and the decline of dislocation density further hinders dislocation motion,which are main responsible for the rise of stress relaxation resistance of Cu-Ni-Sialloy strip.

关 键 词：CU-NI-SI合金 应力松弛 性能 组织 

分 类 号：TG146.11[一般工业技术—材料科学与工程] TG113.25[金属学及工艺—金属材料]