热循环对TC4合金室温和低温拉伸性能的影响  

Effects of thermal cycling on tensile properties of Ti-6Al-4V alloy at room and cryogenic temperatures

作　　者：吕钢[1] 董尚利[1] 王庆民[1] 耿洪滨[1] 何世禹[1] 韩恩厚[2] 

机构地区：[1]哈尔滨工业大学材料科学与工程学院,黑龙江哈尔滨150001 [2]中科院金属研究所,辽宁沈阳110016

出　　处：《材料热处理学报》2009年第2期36-38,共3页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金重点项目(50431020)

摘　　要：采用热机械循环试验装置、材料万能实验机、金相显微镜和扫描电镜考察了经0,100,200和500周次热循环处理的TC4(Ti-6Al-4V)合金在室温(293K)和低温(173K、123K、78K)的拉伸性能及断裂行为。结果表明,随循环次数的增加,TC4合金的室温强度和低温强度升高,低温伸长率略有升高,但500次循环试样在78K拉伸时应力有跃升现象且伸长率显著上升;各种循环和测试条件下,TC4合金的拉伸断裂均呈现典型的塑性特征。Effects of thermal cycling on the tensile properties and fracture behavior of Ti-6Al-4V（TC4） alloy at temperatures ranging from 78K to 293K were evaluated by use of thermal mechanical cycling system, MTS universal testing machine, optical microscope and scanning electron microscopy（SEM）. With increasing thermal cycles, an increase in strength and a slight increase in fracture strain were observed in TC4 alloy at room and cryogenic temperature. Meanwhile, a significant increase of strength and fracture strain was observed for the 500 thermal cycled specimen tested at 78K. The tensile fracture surface of all the as-annealed and thermal cycled specimens exhibits typical ductile fracture features.

关 键 词：钛合金 热循环 拉伸性能 低温 断裂 

分 类 号：TG146.2[一般工业技术—材料科学与工程] TG115.2[金属学及工艺—金属材料]