Experiments were conducted to investigate the overload retardation behavior of fatigue crack growth in FGH96 powder superalloy at 500℃and 700℃under different overload ratios.The effects of test temperature and overload ratio on the crack growth overload retardation behavior of FGH96 alloy were analyzed,and the fatigue crack growth overload retardation behavior of FGH96 was predicted and analyzed.The results show that for FGH96 superalloy,the greater the overload ratio,the more pronounced the overload retardation effect.At the same overload ratio,the overload retardation effect at 700℃is more pronounced than at 500℃.When the overload ratios are 1.2 and 1.4,the overload retardation effect is not significant,and there is little difference between the predictions of the generalized Willenborg model,the modified generalized Willenborg model,and the modified Willenborg model,as well as the experimental results.When the overload ratio is 1.6,the overload retardation effect is significant.The prediction results of the modified Willenborg model for the crack growth curve are in good agreement with the experimental results,with a crack growth lifetime prediction error of less than 10%.The predictions of the generalized Willenborg model and the modified generalized Willenborg model for the crack growth curve are similar and differ significantly from the experimental results,leading to larger differences in crack growth lifetime predictions compared to the experimental results.
关键词
镍基高温合金/裂纹扩展/过载迟滞
Key words
nickel based superalloy/crack growth/overload retardation
维普
万方数据