低浓度Cu-0.5% Nb纳米弥散强化铜合金退火行为的研究  

Annealing behavior of low content niobium nano-particle dispersion strengthened copper alloy

作　　者：雷若姗[1] 汪明朴[1] 郭明星[1] 李周[1] 曹玲飞[1] 陈畅[1] 

机构地区：[1]中南大学材料科学与工程学院,湖南长沙410083

出　　处：《材料科学与工艺》2007年第6期763-766,共4页Materials Science and Technology

基　　金：国家高技术研究发展计划资助项目(2002AA302505);博士点基金资助项目(20040533069)

摘　　要：为了获得具有高强、高导及良好抗高温软化性能的铜合金,用机械合金化法制备了Cu-0.5%Nb纳米弥散强化铜合金.采用力学、电学性能测量、金相、透射电镜观察对该合金退火行为进行了研究.研究表明:随着退火温度的升高,合金硬度呈下降趋势,在900℃以下退火以回复过程为主.该合金相对电导率随退火温度升高而升高,400℃时达到峰值89%IACS;随后不断降低,到800℃时由于Nb的回溶量增加,其降低速率开始加快.TEM观察表明,该合金冷轧态位错密度很高,随退火温度升高不断降低.纳米Nb粒子可强烈阻碍晶界和位错运动,900℃退火后基体仍以亚晶组织为主,合金抗高温软化性能较好.In order to obtain conductors with high strength, high conductivity and high resistance to softening the nano-particle dispersion strengthened copper alloy with niobium content of 0.5% was prepared by mechanical alloying, and its annealing characteristics were invesgigated. The results show that. the hardness decreases slowly with increasing annealing temperature, which indicates that alloy recovery occurs. With annealing temperature increasing,the alloy relative conductivity increases and reaches its maximum 89% IACS at 400℃. However, it decreases with the further increasing annealing temperature, which is mainly caused by the resolution of niobium particles. TEM observation shows that the dislocation density in the cold rolled alloy matrix is very high and decreases with the increasing annealing temperature. As the fine niobium particles are the obstacles to dislocation and grain boundaries motion, the subgrain structure but not recrystal grains is retained in most regions after annealed at 900 ℃. Therefore the alloy has a high softening resistance at elevated temperature.

关 键 词：机械合金化 Cu—Nb合金 退火 回复 再结晶 

分 类 号：TG166.2[金属学及工艺—热处理] TG135.1[金属学及工艺—金属学]