一种新型Er、Zr微合金化Al-Zn-Mg-Cu合金的均匀化处理

Homogenizing Treatment of a New Al-Zn-Mg-Cu Alloy Microalloyed with Er and Zr

研究了4种均匀化工艺对Al-Zn-Mg-Cu-Er-Zr合金的弥散相析出行为和再结晶动力学的影响。结果表明:相比单级均匀化,缓慢升温和双级均匀化处理的合金中弥散相析出特征较优,颗粒相对细小,数量密度和体积分数较高;弥散相析出特征影响合金的抗再结晶性能。经470℃相同时间退火后,4种工艺均匀化处理的合金的再结晶体积分数大小顺序为HT50<HT25≈DHT<HT,与Al3(Er,Zr)弥散相的析出特征基本一致。合金的等温再结晶过程符合Avrami再结晶动力学模型,但实际上仍需考虑弥散相的长大和粗化等因素的影响。

Effects of four kinds of homogenizing processes on the precipitation behavior and recrystallization kinetics of Al-Zn-Mg-Cu-Er-Zr alloy were investigated.The results showed that compared with single-stage homogenizing,the precipitation in the alloy treated by slow-heating and double-stage homogenizing had such characteristics better as smaller size,higher number density and volume fraction.The precipitation characteristics affected the recrystallization resistance of the alloy,and after annealing at 470℃for the same time,the order of recrystallization volume fraction of the alloys homogenized by the four kinds of process was HT50<HT25≈DHT<HT,which was basically consistent with the precipitation characteristics of Al3(Er,Zr)phases.The isothermal recrystallization process of the alloy conformed to the Avrami’s recrystallization kinetic model,but the effect of factors such as growth and coarsening of the precipitates should be considered in practice.