铸造技术2026，Vol.47Issue(2)：176-181,6.DOI:10.16410/j.issn1000-8365.2026.5093
钛铝合金高温-超高周疲劳行为研究
Study of the Very High Cycle Fatigue Behavior of TiAl Alloy at Elevated Temperatures
摘要
Abstract
As novel lightweight high-temperature structural materials,titanium aluminide alloys exhibit excellent high-temperature strength,oxidation resistance,and creep resistance.It is considered the preferred material to replace nickel-based superalloys.As an elevated-temperature structural component,it is subjected to both elevated temperatures and cyclic loads during service,necessitating research into its fatigue behavior at elevated temperatures.Ultrasonic fatigue testing,an efficient means of fatigue testing,can greatly reduce the time cost of detailed analysis of alloy fatigue failure mechanisms.Accordingly,by combining ultrasonic fatigue testing equipment and a medium high-frequency induction heating device,the cyclic deformation behavior of the Ti-48Al-2Cr-2Nb alloy at 650 ℃ was investigated.The results show that there is no fatigue limit for Ti-48Al-2Cr-2Nb at 650 ℃.The fracture mode is a mixture of quasicleavage fracture and intergranular fracture,where cracks initiate near the cleaved γ grains and propagate along grain boundaries.Near the lamellar groups,the fracture mode is a mixture of trans-and interlamellar fractures.As the amplitude of the cyclic stress decreases,the failure mode transitions from fracture caused by long crack linkages following short crack propagation to fracture resulting from the interconnection of short cracks forming long cracks,leading to a reduction in fatigue life dispersion and a decrease in fracture surface roughness.关键词
Ti-48Al-2Cr-2Nb合金/高温拉伸/高温超高周疲劳/疲劳失效机制Key words
Ti-48Al-2Cr-2Nb alloy/elevated-temperature tensile/very high-temperature cycle fatigue/fatigue failure mechanism分类
矿业与冶金引用本文复制引用
曹喜川,李凯迪,邵泓铨,何季华,唐斌..钛铝合金高温-超高周疲劳行为研究[J].铸造技术,2026,47(2):176-181,6.基金项目
国家重点研发计划(2021YFB3702602) （2021YFB3702602）
