Crack initiation anisotropy of Ni-based SX superalloys in the very high cycle fatigue regime

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:825

Article

Cervellon, Alice¹  Torbet, Chris J.¹  Pollock, Tresa M.¹ 

[1] Univ Calif Santa Barbara, Dept Mat, Santa Barbara, CA 93106 USA

关键词: Very high cycle fatigue;    Superalloys;    Anisotropy;    Pseudo-cube slip;    Crack initiation;   

DOI  :  10.1016/j.msea.2021.141920

来源: Elsevier

【 摘 要 】

The anisotmpic fatigue properties of three Ni-based SX superalloys (AM1, CMSX-4 and MC-NG) were investigated in the very high cycle fatigue regime at 20 kHz, R = -1 and 750 degrees C. The fatigue testing shows that the [111] orientation has higher fatigue lives at high stresses and lower fatigue lives at very low stresses compared to the standard [001] orientation. At high stresses, the resolved shear stress on the octahedral slip systems explains the anisotropy effect. At low stresses, pseudo-cube slip in the matrix becomes the prominent deformation mechanism over gamma'-shearing in the [111] orientation, resulting in comparatively lower fatigue properties.

【 授权许可】

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