Decoupling of Strain and Temperature Effects on Microstructural Evolution During High Shear Strain Deformation

The interplay between defect generation by shear strain and defect annihilation by local heating is difficult to predict in shear-assisted processing techniques. Here, we decoupled the effects of high shear strain and external heating in an immiscible Cu-Nb alloy using a pin-on-disk tribometer to mimic the microstructural evolution of material during solid-phase processing. The change in sub-surface deformation, strain distribution, and redistribution of the second phase as a function of temperature were examined using transmission electron microscopy and atom probe tomography. Zener-Hollomon parameter is used to semi-quantify the deformation of Cu-Nb alloys as a function of strain and temperature.