航空学报2025，Vol.46Issue(21)：117-130,14.DOI:10.7527/S1000-6893.2025.32364
高温条件下FGH4108合金的保载-疲劳裂纹扩展行为
Dwell-fatigue crack growth behavior of FGH4108 alloy at high temperature
摘要
Abstract
Fatigue crack growth experiments and interrupted tests are conducted on the fourth-generation powder metallurgy superalloy FGH4108 under varying temperatures and dwell time.The influence of temperature and dwell time on crack growth behavior is analyzed using characterization techniques such as Scanning Electron Microscopy(SEM),Electron Backscatter Diffraction(EBSD),and Electron Probe Microanalysis(EPMA).The mechanism by which oxidation damage affects crack growth is revealed.A fatigue crack growth rate model describing the mechanical-oxidation coupling effect is proposed.The results show that as temperature and dwell time increase,the crack growth rate rises and fatigue life decreases significantly.Fractographic analysis reveals that at 650℃,fatigue cracks primarily propagate transgranularly with relatively flat fracture surfaces,while at temperatures above 750℃,fatigue cracks mainly propagate intergranularly,accompanied by the formation of secondary cracks.Concurrently,phenomena such as alterations in crack tip morphology and oxide formation were observed during crack propagation,elucidating the im-pact of oxidation on crack growth.The proposed model can better describe the fatigue crack growth rate at different temperatures and dwell time.At the same time,the effects of mechanical damage and oxidative damage on crack growth are decoupled,and the temperature dependence of oxidative damage parameters is determined.关键词
粉末高温合金/氧化损伤/疲劳裂纹扩展/裂纹扩展速率模型/高温Key words
powder metallurgy superalloy/oxidation damage/fatigue crack propagation/crack propagation rate model/high temperature分类
航空航天引用本文复制引用
秦豪,刘强,江荣,宋迎东,张强,刘建涛,邓健,卢天健..高温条件下FGH4108合金的保载-疲劳裂纹扩展行为[J].航空学报,2025,46(21):117-130,14.基金项目
国家自然科学基金(12272174) （12272174）
国家科技重大专项(2017-Ⅵ-0008-0078) （2017-Ⅵ-0008-0078）
江苏省双创团队(JSSCTD202206) （JSSCTD202206）
江苏省自然科学基金(BK20220136) （BK20220136）
航空发动机及燃气轮机基础科学中心重点项目(P2022-B-Ⅲ-007-001) National Natural Science Foundation of China(12272174) （P2022-B-Ⅲ-007-001）
National Science and Technology Major Project(2017-Ⅵ-0008-0078) （2017-Ⅵ-0008-0078）
Innovation and Entrepreneurship Teams of Jiangsu Province(JSSCTD202206) （JSSCTD202206）
Natural Science Foundation of Jiangsu Province(BK20220136) （BK20220136）
Key Project of the Basic Science Center for Aero Engines and Gas Turbines(P2022-B-Ⅲ-007-001) （P2022-B-Ⅲ-007-001）
