连续纤维晶纯铜高温与低温退火的对比研究

Comparative study on high temperature and low temperature annealing of pure copper containing continuous fibrous crystals

采用电子背散射衍射技术对比研究了经大变形冷拔后的连续纤维晶纯铜线材860℃×30 s高温短时退火与400℃×1 h低温长时退火其微观组织、织构和晶界特征分布以及力学性能和导电性能的变化规律。结果表明:经860℃退火30 s后铜样品基本完成再结晶,其晶粒平均直径为20μm与400℃×1 h退火结果 25μm相差不大,且两者的织构均为较明显的<100>丝织构;860℃退火30 s后其重合位置点阵(Coincidence Site Lattice,CSL)晶界量可达51%明显高于400℃退火处理结果 35%。高温退火后的抗拉强度和导电率与低温大致相当,高温退火和低温退火后铜线的导电率均达到较高水平分别为103.29%IACS和101.50%IACS。因此,连续纤维晶纯铜线材经860℃高温短时退火后获得的力学性能和导电性能不低于低温退火。

Microstructure,texture,coincidence site lattice（CSL）,mechanical properties and electrical conductivity of pure copper wires containing continuous fibrous crystals,which were annealed at 860 ℃ for 30 s and 400 ℃ for 1 h,were investigated by electron back scattered diffraction（EBSD） technique.The results show that after annealing at 860 ℃ for 30 s,the sample has almost finished recrystallization and the average grain size of the samples annealed at high temperature is 20 μm which is a little smaller than that of annealed at 400 ℃ for 1 h.The samples annealed at high and low temperature both have a 100 fiber texture.The fraction of CSL boundaries after annealing at 860 ℃ can reach 51%,which is much higher than that of low temperature annealing（35%）.Mechanical properties and electrical property of the copper wires annealed at high temperature are almost the same with that of low temperature.The electrical conductivities of the copper wires annealed at high temperature and low temperature are both at a high level,which are 103.29% IACS and 101.50 % IACS,respectively.Therefore,the mechanical properties and electrical conductivity of the copper wires containing continuous fibrous crystals that annealed at high temperature of 860 ℃ are not worse than that of annealed at low temperature.