摘要
在不同温度下对Al—Cu合金试件进行固溶处理,以改变溶质原子在固溶体中的浓度及析出相在合金中的含量．对所得到的Al—Cu合金试件进行常应变率拉仲实验,观察其应力-时间关系曲线．由拉伸实验现象分析溶质原子及析出相对位错运动的影响,从而探究Portevin—Le Chatelier(PLC)效应产生的微观机制．结果表明,当固溶处理温度由500℃逐步降低,应力-时间曲线上的锯齿幅值逐渐减小,并在300℃时达到最小值;继续降低固溶处理温度至100℃,锯齿幅值又逐渐增大．固溶处理温度高于300℃时,溶质原子对PLC效应的影响强于析出相的影响而起主要作用;反之,固溶处理温度低于300℃时,析出相对PLC效应的影响强于溶质原子的影响而起主要作用．
The solute concentration and precipitated phase content in Al-Cu alloy were altered by solution treatment at different temperatures. A series of serrated stress-time curves was obtained in tensile tests at a constant strain rate. The influences of solute concentration and precipitated phase content on dislocation movement were analyzed with tensile test results, and the micro-mechanism of Portevin-Le Chatelier （PLC） effect was discussed. When solution treatment temperature is reduced from 500 ℃, the amplitude of serrated flow decreases, and reaches the minimum when solution treatment temperature is reduced to 300 ℃. On the contrary, the amplitude of serrated flow increases with solution treatment temperature decreasing continuously from 300 to 100 ℃. Experimental results show that, when solution treatment temperature is higher than 300 ℃, solute concentration is a governing factor to PLC effect, whereas when solution treatment temperature is lower than 300 ℃, the precipitated phase content affects dominantly PLC effect.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2006年第12期1248-1252,共5页
Acta Metallurgica Sinica
基金
国家自然科学重点基金项目10232030和10372098资助~~
