# Dynamic Softening Mechanism of Platinum Thermomechanically Deformed at Low Strain Rate

## TL;DR

This study explores how pure platinum softens during deformation at high temperatures and low strain rates.

## Contribution

The paper identifies dynamic recovery as the main softening mechanism in platinum during thermal deformation.

## Key findings

- Grain size and dislocation density decrease with increasing deformation temperature.
- Dynamic recovery based on dislocation cross-slip/climb is the primary softening mechanism.
- Continuous and geometric dynamic recrystallization improve microstructural homogeneity above 650 °C.

## Abstract

The mechanical behavior of pure Pt at elevated temperatures is critical for its high-temperature processing and applications. To understand its thermal deformation behavior and reach better processing control, thermal compression deformation was conducted for pure Pt in this work with a strain rate of 0.01 s−1 and temperatures ranging from 500 to 700 °C, followed by microstructure characterization by using electron backscatter diffraction (EBSD) technique. The results indicate that the grain size, fraction of low-angle grain boundaries, and dislocation density are generally reduced with increasing temperature. An analysis combining true stress–strain curves and microstructural characteristics indicates that dynamic recovery based on dislocation cross-slip/climb is always a main softening mechanism of pure Pt during thermal deformation. Continuous dynamic recrystallization and geometric dynamic recrystallization also occur when the deformation temperature exceeds 650 °C, which will effectively improve the microstructural homogeneity of pure Pt.