高温低周疲劳损伤对FGH96合金力学性能影响  

Effects of High Temperature Low-Cycle Fatigue Damage on Mechanical Properties of FGH96 Alloy

作　　者：李政广 徐可君 秦海勤 肖阳 Li Zhengguang;Xu Kejun;Qin Haiqin;Xiao Yang(Naval Aviation University(Qingdao Campus),Qingdao 266041,China;91213 Troops of PLA,Yantai 264000,China)

机构地区：[1]海军航空大学青岛校区,山东青岛266041 [2]中国人民解放军91213部队,山东烟台264000

出　　处：《稀有金属材料与工程》2023年第7期2511-2518,共8页Rare Metal Materials and Engineering

摘　　要：通过设计FGH96粉末高温合金的高温低周疲劳试验和高温单轴拉伸试验,研究了不同应力水平下高温低周疲劳损伤对合金力学性能的影响,结合对断口形貌的观察和成分分析,分析了合金力学性能改变的微观机理。结果表明,受疲劳载荷作用期间位错运动的影响,合金的屈服强度、抗拉强度在损伤前期表现出上升的趋势;损伤后期,随着材料内部裂纹的不断增多及扩展,合金的弹性模量、抗拉强度不断退化。合金力学性能的变化与疲劳加载的应力水平表现出明显的相关性。断口显微组织分析表明,随着损伤程度的增加,合金高温拉伸断裂模式由韧性逐渐向脆性转变,高温氧化加速了断裂模式的转变。High temperature low-cycle fatigue test and high temperature tensile test were designed to study the effects of high temperature low-cycle fatigue damage on mechanical properties of FGH96 powder metallurgy superalloy.The microscopic mechanism of the mechanical properties changes of FGH96 alloy was analyzed by observing the fractographs and EDS elements analysis.Results show that the yield and tensile strength show an upward trend in the early stage of damage due to the effects of dislocation motion;in the later stage of damage,the elastic modulus and tensile strength continuously decrease when the internal cracks increase and expand.The change of the mechanical properties shows a clear correlation with the stress level of fatigue test.The microstructure analysis results show that with increasing the damage degree,the high temperature tensile fracture mode gradually changes from the ductile to the brittle,and the fracture is accelerated by high temperature oxidation.

关 键 词：粉末高温合金 高温低周疲劳 拉伸性能 疲劳损伤 断口分析 

分 类 号：TG132.3*3[一般工业技术—材料科学与工程]