CAJ | 학술논문

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。
통과투사전경관찰화XRD검측분석，대비순Al시양，연구료다향압축변형(MAC)과정중고용원자급석출상대Al-4Cu합금정립세화효과적영향。결과표명：실온하，경과상동변형도차후，고용원자적존재도치Al-4Cu합금소형성적아정립형모불규칙，정내위착밀도교고，정장약200 nm、관약100 nm적류죽절상，순Al중아정립내부위착밀도저，정직경약600 nm적등축상；Al-4Cu합금재실온하적석출상회용과정억제세소정립적형성，유리우아정내부위착밀도적강저，50℃하적석출상회용급재석출과정유리우세소정립적형성。
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.