In situ XRD studies of the process dynamics during annealing in cold rolled copper

TL;DR

This study investigates the in-situ dynamics of stored energy release during annealing of deformed copper along specific crystallographic planes using XRD, microstructural analysis, and calorimetry, revealing recovery and recrystallization behaviors.

Contribution

It provides a detailed in-situ analysis of energy release and microstructural evolution during annealing in cold-rolled copper, employing advanced XRD and modeling techniques.

Findings

Stored energy release varies with crystallographic plane and deformation level.

Recovery follows a second-order process, recrystallization follows a first-order process.

Microstructural parameters correlate with energy release during annealing.

Abstract

The dynamics of the release of stored energy during annealing along two different crystallographic planes i.e.{111} and {220} in deformed copper have been investigated using in-situ X-ray diffraction measurements at 458K and 473K respectively. The study has been carried out on 50% and 80% rolled Cu sheets. The microstructures of the rolled samples have been characterised using optical microscope and Electron Back Scattered Diffraction measurements. The microstructural parameters were evaluated using Scherrer equation and the modified Rietveld technique from X-ray diffractogram. The stored energy along different planes were determined using the modified Stibitz formula from the X-ray peak broadening and the bulk stored energy has been evaluated using differential scanning calorimetry. The process dynamics of recovery and recrystallization as observed through the release of stored energy has been modelled as a second order and first order process respectively.