TiAl＋Ca合金断裂及变形亚结构研究  

FRACTURE AND DEFORMATION SUBSTRUCTURE OF TiAl+Ca ALLOY

作　　者：曹鹏[1] 贺跃辉[1] 黄伯云[1] 

机构地区：[1]中南工业大学粉末冶金国家重点实验室

出　　处：《中南工业大学学报》1996年第6期703-706,共4页Journal of Central South University of Technology(Natural Science)

基　　金：国家自然科学基金;国家"八六三"高技术研究计划资助

摘　　要：运用ＳＥＭ和ＴＥＭ等分析手段研究了ＴｉＡｌ＋Ｃａ三元合金的室温断裂行为和变形亚结构．结果表明，少量Ｃａ的添加可以大幅度提高Ｔｉ－３４％Ａｌ合金的室温力学性能．合金断裂时不再表现为单纯的穿晶解理断裂而在γ单相中出现了河流状的解理纹，断口上还出现较多的撕裂梭；ＴＥＭ分析表明，Ｃａ的添加有助于１／２＜１１０］正常位错的启动；Ｔｉ－３４％Ａｌ－１．０％Ｃａ合金压缩变形时产生大量的位错环，当Ｃａ含量达到２．０％时，在γ相中出现了由于位错分解而产生的层错．The fracture behaviors and deformation substructures of TiAl+Ca alloy were investigated using SEM and TEM. The results show small Ca additions to Ti-34%Al can improve remarkedly its mechanical properties at ambient temperature. The fracture mode is a mixed mode, including transgranular cleavage and 'river' pattern in gamma single phase. A lot of tear ridges can be found in the fractured surfaces. TEM results indicate Ca additions can enhance the activity of ordinary unit dislocation 1/2 <110]. Dislocation loops in Ti-34%Al-1.0%Ca alloy and stack faults resulting from superdislocation dissociation in Ti-34%Al-2.0%Ca alloy, were observed.

关 键 词：合金化 断裂 位错 变形亚结构 铝基合金 钛合金 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG146.23[金属学及工艺—金属材料]