Microstructural‐based strain accumulation during cyclic loading of Ni‐based superalloys: The role of neighboring grains on interconnected slip bands

Abstract

Cyclic loading of polycrystalline materials results in the localization of strain relative to microstructural features. In this work, strains characterized from digital image correlation were used to calculate a value for the incremental slip on the active slip systems and identify cases of slip transmission. Interconnected slip bands, between neighboring grains, were shown to accumulate more incremental slip (and associated strain) compared with slip bands confined to a single grain, where slip transmission did not occur. These results rationalize the role of grain clusters leading to intense strain accumulation and thus serving as potential sites for fatigue crack initiation.