Al-Sc-Zr合金中析出相的形成及再结晶抑阻

摘要

Al-x％Sc-0.1l％Zr alloys (x=0,0.02,0.05,0.08,0.11,0.15) were produced by a chill cast procedure.The effect of Sc content on the precipitation of Al3(Sc,Zr) during heat treatment at 475 ℃ for 12 h was studied.Nucleation,precipitation and distribution of Al3(Sc,Zr) precipitates were found to be strongly related to the Sc content.With increasing the Sc content,the average radius of the precipitates decreases,while the number density of the precipitates increases,as investigated by transmission electron microscopy (TEM).The distribution of the precipitates becomes more and more homogeneous when the Sc content is increased.The recrystallization resistance of samples that was 90％ cold rolled and isothermal annealed for half an hour in the temperature range of 200-600 ℃ was investigated.The results show that the recrystallization temperature varies from 250 ℃ for the alloy without Sc to about 600 ℃ for the alloy containing 0.15％ Sc because of the high density of Al3(Sc,Zr) precipitates.%通过冷硬铸造法制备Al-x％Sc-0.11％Zr合金(x=O,0.02,0.05,0.08,0.11,0.15),研究合金在475℃保温12 h热处理条件下不同钪含量对Al3(Sc,Zr)析出的影响.研究发现,Al3(Sc,Zr)析出相的形核、析出和分布与钪含量密切相关.透射电子显微镜研究表明,随着钪含量的增加,析出相的平均半径减小,密度增大,分布变得越来越均匀.将90％冷轧样品在200～600℃的温度区间等温退火0.5 h,再进行抗再结晶能力的研究.结果表明,未添加钪的合金的再结晶温度为250℃,而添加0.15％钪后形成的Al3(Sc,Zr)析出相使得再结晶温度升高到约600℃.