Ecap was successfully used to refine ly12 alloy to 0 . 5 m at room temperature after seven passes . the pretreatment process concluded from experiments was solution treated at 500 for 2h and overaging at 400 for 8h 对普通高强度铝合金ly12的室温ecap的研究表明: ecap前的预处理对ly12室温ecap的实现具有重要影响,采用500 2h固溶+ 400 8h过时效的预处理工艺,经七道次室温ecap后,晶粒细化至0 . 5 m 。