摘要
采用应变控制的方法,研究了铸造Ti-48Al-2Cr-2Nb合金400℃~800℃循环温度下的同相位热机械疲劳行为,并与400℃和800℃恒温低周疲劳结果进行了对比分析。结果表明,该合金的400℃~800℃同相位热机械疲劳性能在大应变短寿命区优于400℃和800℃恒温低周疲劳;在小应变长寿命区略低于400℃低周疲劳,介于800℃低周疲劳数据分散带内;在热机械疲劳试验条件下,合金不表现明显循环硬化或软化现象,疲劳试样断口可观察到层片间、层片内断裂和穿层片撕裂3种开裂方式。
The thermo-mechanical fatigue(TMF)behavior of casting alloy Ti-48 Al-2 Cr-2 Nb was researched.The tests were performed thermo-mechanically in-phase(IP)at 400℃~800℃.During TMF,tests strain was controlled.The result of this IP TMF was compared with 400℃and 800℃isothermal low cycle fatigue(LCF).The result shows that the fatigue life of Ti-48 Al-2 Cr-2 Nb alloy in 400℃~800℃TMF condition is longer than 400℃and 800℃LCF within high strain region.Within low strain region,it is slightly shorter than 400℃LCF and within the dispersion zone of 800℃LCF.In this TMF condition,no evidence shows hardening or softening phenomenon.SEM analysis shows that inter-lamellar and inner-lamellar cracking and trans-lamellar tearing can be observed on the fracture surface.
作者
钟斌
焦泽辉
郑飞
马岳
苏彬
ZHONG Bin;JIAO ZeHui;ZHENG Fei;MA Yue;SU Bin(AECC Key Laboratory of Aeronautical Materials Testing and Evaluation,Science and Technology on Advanced High Temperature Structural Materials Laboratory,Beijing Key Laboratory of Aeronautical Materials Testing and Evaluation,Beijing Institute of Aeronautical Materials,Beijing 100095,China;School of Material Science and Engineering,Beihang University,Beijing 100091,China)
出处
《机械强度》
CAS
CSCD
北大核心
2020年第3期559-564,共6页
Journal of Mechanical Strength
基金
航空科学基金项目(2013ZF21014)资助。
