Influence of grain size on the small fatigue crack initiation and propagation behaviors of a nickel-based superalloy at 650℃

作者：Xumin Zhu; Congyang Gong; Yun-Fei Jia; Runzi Wang; Chengcheng Zhang; Yao Fu; Shan-Tung Tu; Xian-Cheng Zhang

来源：Journal of Materials Science & Technology, 2019, 35(08): 1607-1617.

GH4169 at 650℃ in atmosphere was investigated by using single edge notch tensile specimens. The number of main cracks and crack initiation mechanisms at the notch surface strongly depended on the grain size. The crack initiation life accounted for more percentages of the total fatigue life for the alloy with smaller grain size. The fatigue life generally increased with increasing crack initiation life. The small crack transited to long crack when its length reached 10 times the grain size.

• 单位
  华东理工大学