The role of slip transfer at grain boundaries in the propagation of microstructurally short fatigue cracks in Ni-based superalloys

SCRIPTA MATERIALIA

卷:162

Article

Jimenez, M.^1,2  Ludwig, W.^3,4  Gonzalez, D.⁵  Molina-Aldareguia, J. M.¹ 

[1] IMDEA Mat Inst, C Eric Kandel 2, Madrid 28906, Spain

[2] Univ Carlos III Madrid UC3M, Dept Mat Sci & Engn, Leganes 28911, Spain

[3] Univ Lyon, INSA Lyon, Mateis, UMR CNRS 5510, Lyon, France

[4] European Synchrotron Radiat Facil, F-38043 Grenoble, France

[5] Univ Birmingham, Sch Met Mat, PRISM2 Res Grp, Birmingham B15 2TT, W Midlands, England

关键词: X-ray synchrotron radiation;    Grain boundary;    High cycle fatigue;    Superalloy;    Microstructurally short crack propagation;   

DOI  :  10.1016/j.scriptamat.2018.11.008

来源: Elsevier

【 摘 要 】

Crack initiation and propagation under high-cycle fatigue conditions have been investigated for a polycrystalline Ni-based superalloy by in-situ synchrotron assisted diffraction and phase contrast tomography. The cracks nucleated along the longest coherent twin boundaries pre-existing on the specimen surface, that were well oriented for slip and that presented a large elastic incompatibility across them. Moreover, the propagation of microstructurally short cracks was found to be determined by the easy slip transfer paths across the pre-existing grain boundaries. This information can only be obtained by characterization techniques like the ones presented here that provide the full set of 3D microstructural information. (C) 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

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