Experimental and modelling study of fatigue crack initiation in an aluminium beam with a hole under 4-point bending

INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

卷:138

Article

Ye, Wenye^1,2  Efthymiadis, Panos^2,3  Pinna, Christophe³  Ma, Anxin¹  Shollock, Barbara²  Dashwood, Richard⁴ 

[1] Ruhr Univ Bochum, Interdisciplinary Ctr Adv Mat Simulat, Univ Str 90 A, D-44789 Bochum, Germany

[2] Univ Warwick, Warwick Mfg Grp, Int Mfg Ctr, Coventry CV4 7AL, W Midlands, England

[3] Univ Sheffield, Dept Mech Engn, Mappin St, Sheffield S1 3JD, S Yorkshire, England

[4] Coventry Univ, Vice Chancellors Off, Coventry CV1 5FB, W Midlands, England

关键词: crack initiation;    slip band;    crystal plasticity;    4-points bending test;    Fatigue indicating parameter;   

DOI  :  10.1016/j.ijsolstr.2018.01.001

来源: Elsevier

【 摘 要 】

Slip band formation and crack initiation during cyclic fatigue were investigated by in-situ experiments and non-local CPFEM simulations systematically. Experimental techniques including EBSD, digital image correlation (DIC) and SEM have been used to obtain consistent grain orientations, local strains, as well as the locations where slip bands and micro-cracks form on the sample surface. The realistic microstructure based on the EBSD map has been generated and used for finite element modelling. An advanced non local crystal plasticity model, which considers the isotropic and kinematic hardening of the plastic strain gradient, has been adopted. The simulation results match well the corresponding experimental results. It was found that total strain and averaged slip on all slip systems, combined with accumulated slip on specific slip planes help predict the location and orientation of slip bands and micro-crack initiation correctly. Furthermore, a fatigue indicating parameter based on competition between maximum slip and the total slip has been proposed to reproduce the experimental observations. Crown Copyright (C) 2018 Published by Elsevier Ltd.

【 授权许可】

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