Measurement of local plastic strain during uniaxial reversed loading of nickel alloy 625

Michael D Atkinson, Jack Donoghue, João Quinta da Fonseca
2020 Zenodo  
The development and evolution of plastic strain localisation was measured at sub-micron resolution using high-resolution digital image correlation (HRDIC) during reverse loading of a solid solution strengthened nickel base superalloy. The deformation was applied in-situ, allowing measurements to be taken with load applied which will not include any reverse yielding that can occur during unloading due to the Bauschinger effect. The strain was found to be localised into crystallographic slip
more » ... lographic slip bands separated by lower strain channels. No large local deformation was seen when unloading the material following forward deformation. Analysis of the unload strains, at the grain level, showed that any non-linearity seen in the macroscopic unload curve is either due to elastic anisotropy or low magnitude plastic deformation. The slip band structures formed in forward loading did not change during the early stages of reversal, suggesting reverse deformation is accommodated by dislocations reversing their paths. After further reverse deformation, the slip band patterns appear to change in location and become more sharply defined.
doi:10.5281/zenodo.3765189 fatcat:wzbm4yucajavbo2cxc4npkctyy