首页|Influence of welded pores on fatigue behavior of TC17 titanium alloy welded joints subjected to gigacycle regime at room and high temperatures

Influence of welded pores on fatigue behavior of TC17 titanium alloy welded joints subjected to gigacycle regime at room and high temperatures

扫码查看
原文链接
  • NETL
  • NSTL
  • 万方数据
Welded structures in aero-engines commonly operate in high-temperature environments,making them susceptible to reduced fatigue life and premature failure due to welding defects within the structure.Thus,the gigacycle fatigue behaviors of titanium alloy welded joints at both room temperature(RT)and 400 ℃ were investigated,aiming to uncover the mechanism behind the formation of fine granular area(FGA)surrounding welded pores.The research findings demonstrate that the S-N curves of TC17 tita-nium alloy electron beam welded joint undergo a transition from a single linear decline at RT to a bilin-ear decline at 400 ℃.However,the fatigue failure mode remains unaffected by temperatures,and crack initiation is attributed to welded pores.By utilizing the Chapetti model curve to modify the Kitagawa-Takahashi(K-T)diagram,the lower threshold stress amplitude is introduced,enabling the determination of a safe size for welded pores at 400 ℃,which is calculated to be 11.3 μm.Additionally,the Gumbel probability distribution function is employed to assess the maximum size of welded pores.Finally,based on dislocation interactions,the formation mechanism of the FGA consisting of discontinuous nanograins with high-density dislocations is elucidated.

Titanium alloyWelded jointsGigacycle fatigueWelded poresHigh temperatureFine granular area

Fulin Liu、Yao Chen、Lang Li、Chong Wang、Qingyuan Wang、Yongjie Liu

展开 >

MOE Key Laboratory of Deep Earth Science and Engineering,College of Architecture and Environment,Sichuan University,Chengdu 610065,China

Failure Mechanics and Engineering Disaster Prevention Key Laboratory of Sichuan Province,Sichuan University,Chengdu 610207,China

Department of Mechanical Engineering,Kyushu University,Fukuoka 819-0395,Japan

National Natural Science Foundation of ChinaNational Natural Science Foundation of ChinaNational Natural Science Foundation of ChinaNational Natural Science Foundation of ChinaFundamental Research Funds for the Central Universities of Sichuan UniversitySichuan Province Science and Technology Project

12172238118320071202220812102280CJ2022072022JDJQ0011

2024

10.1016/j.jmst.2023.09.006

材料科学技术(英文版)
中国金属学会 中国材料研究学会 中国科学院金属研究所

材料科学技术(英文版)

CSTPCD
影响因子：0.657
ISSN：1005-0302
年,卷(期)：2024.178(11)
  • 62