固溶原子及析出相对强变形Al-4Cu合金晶粒细化效果的影响  

Effect of solute atom and precipitated phase on grain refinement of Al-4Cu alloy by severe plastic deformation

作　　者：赵凤晓[1] 许晓嫦[1,2] 张奇[1] 徐浩浩[1] 刘海全[1] 曾慧颖 

机构地区：[1]中南大学材料科学与工程学院,长沙410083 [2]中南大学有色金属材料科学与工程教育部重点实验室,长沙410083

出　　处：《中国有色金属学报》2014年第2期395-402,共8页The Chinese Journal of Nonferrous Metals

基　　金：国家重点基础研究发展计划资助项目(2012CB619506-2)

摘　　要：通过透射电镜观察和XRD检测分析,对比纯Al试样,研究了多向压缩变形(MAC)过程中固溶原子及析出相对Al-4Cu合金晶粒细化效果的影响。结果表明:室温下,经过相同变形道次后,固溶原子的存在导致Al-4Cu合金所形成的亚晶粒形貌不规则,晶内位错密度较高,呈长约200 nm、宽约100 nm的类竹节状,纯Al中亚晶粒内部位错密度低,呈直径约600 nm的等轴状;Al-4Cu合金在室温下的析出相回溶过程抑制细小晶粒的形成,有利于亚晶内部位错密度的降低,50℃下的析出相回溶及再析出过程有利于细小晶粒的形成。The size and morphology of pure Al and Al-4Cu alloy processed by multi-axial compression （MAC） deformation were characterized by transmission electron microscopy and X-ray diffractometry to investigate the effect of solute atom and precipitated phase on grain refinement of Al-4Cu alloy by severe plastic deformation. The results show that the existence of solute atom in Al-4Cu alloy is associated with the irregular morphology of subgrain and higher dislocation density than that of pure Al. However, the former in bamboo-like shape exhibits smaller grain size with a length of about 200 nm and a width of about 100 nm than the latter in equiaxed shape with a diameter of about 600 nm. Also, at room temperature grain refinement is suppressed by the re-dissolution of severely deformed precipitated phase, which is helpful to the decrease of dislocation density, and at 50℃the re-dissolution and re-precipitation of precipitate phase contributes to the grain refinement.

关 键 词：Al-4Cu合金 强变形 析出相回溶 晶粒尺寸 亚晶 

分 类 号：TG37[金属学及工艺—金属压力加工]