单多轴变幅加载下TC21钛合金疲劳特性  

Fatigue Properties of TC21 Ti-Alloy under Uniaxial and Multiaxial Cyclic Variable Amplitude Loading

作　　者：田玉杰[1] 尚德广[1] 陈宏[1] 刘建中[2] 

机构地区：[1]北京工业大学机械工程与应用电子技术学院,北京100124 [2]北京航空材料研究院,北京100095

出　　处：《航空材料学报》2013年第2期74-80,共7页Journal of Aeronautical Materials

基　　金：国家自然科学基金资助项目(50975005;51010006);北京市自然科学基金资助项目(3092003);北京市教育委员会科技计划重点项目(KZ201010005003)

摘　　要：在应变载荷控制下对TC21钛合金薄壁管光滑试件进行单轴、拉-扭比例、非比例恒幅、变幅加载试验,研究其疲劳行为。研究表明,TC21钛合金在单轴和多轴比例恒幅载荷下均表现为循环软化,并且应变载荷水平越大软化越明显。非比例变幅加载时,前期的大应变载荷对材料的轴向拉压特性具有强化作用,使得后期小应变载荷下的循环特性出现硬化现象。The fatigue properties of TC21 Ti-alloy for thin-wall tube specimen are investigated under uniaxial, tension-torsion propor- tional, non-proportional and variable amplitude loading. All tests are strain-controlled. The results indicate that cyclic softening behavior is shown for TC21 alloy under uniaxial and proportional tension-torsion constant amplitude loading, and the cyclic softening is more obvious under large strain amplitude loading. The large strain loading followed by small strain loading under non-proportional loading, shows that the cyclic hardening for tension stress is responded in the smaller strain loading stage due to the previous larger strain loading strengthening for tensional properties.

关 键 词：多轴疲劳 比例加载 非比例加载 变幅加载 循环软化和硬化 

分 类 号：TH11[机械工程—机械设计及理论]