摘要
采用光学显微镜(OM)、扫描电镜(SEM)和X射线衍射谱仪研究了固溶处理对高纯7055铝合金组织的影响。结果表明:合金固溶时,粗大的初生AlZnMgCu相溶解缓慢,并逐渐球化;而初生AlZnMgCuFeTi相几乎不溶解。固溶温度越高(460-480℃),时间越长(0-240min),初生AlZnMgCu相溶解越多,再结晶越多,晶粒尺寸越大。再结晶主要于初始晶界上的粗大初生相上形核(PSN机制),并向弥散Al3Zr粒子少的变形晶粒内部长大。490℃固溶时,出现过烧组织,晶粒粗大。分级固溶较单级固溶可更好的控制合金组织,如460℃×120min+480℃×60min与480℃×180min相比,再结晶和晶粒尺寸小得多,但初生AlZnMgCu相溶解程度相差不大。
Optical microscopy (OM), scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to investigate the effects of solution heat treatment on microstructure of a high-purity 7055 aluminum alloy. The AlZnMgCu phase dissolves slowly during solution heat treatment while AlZnMgCuFeTi phase does not dissolve. Higher solution temperature and longer solution time led to more dissolution of AIZnMgCu phase but larger fraction of recrystallization and coarse grain size. Over-heated structure is formed for solution treatment at 490°C. Compared with single solutioning, duplex solutioning results in more dissolution of AIZnMgCu phase without much increase of recrystallization fraction and grain size.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2006年第3期54-59,共6页
Transactions of Materials and Heat Treatment
基金
国家重点基础研究发展计划(2005CB623700)
国家自然科学重点基金(50230310)
博士点基金(2004053304)
关键词
高纯7055铝合金
固溶
初生AlZnMgCu相
再结晶
Dissolution
Heat treatment
Microstructure
Optical microscopy
Recrystallization (metallurgy)
Scanning electron microscopy
Solutions
X ray diffraction analysis
