Surface Roughness Based Characterization of Slip Band for Damage Initiation in a Nickel Base Superalloy

Hsin shen HO, Marion RISBET, Xavier FEAUGAS, Maxence BIGERELLE, Erliang ZHANG


This work presents a computational protocol, based on a variance analysis integrated with the bootstrap method, to investigate surface damage resulting from localization of plastic deformation in slip bands of a Ni-base superalloy. For assessment of fatigue crack initiation, surface roughness is introduced to quantify the degree of slip irreversibility. The contribution of this study is to provide a most relevant roughness parameter that can extract the salient features of slip bands within damaged grains, and thus enabling the discrimination of damaged and undamaged grains for description of fatigue-induced surface damage. Results suggest that the maximum peak height (Sp) is the most relevant parameter. And a very pronounced variability of Sp values is observed for damaged grains.



surface roughness; surface damage; plastic strain localization; atomic force microscopy; Ni-base superalloy

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Print ISSN: 1392–1320
Online ISSN: 2029–7289