Plastic deformation of the CaMg$_{2}$ C14-Laves phase from 50-250$^\circ$C

TL;DR

This study investigates how the CaMg₂ intermetallic phase deforms at temperatures between 50°C and 250°C, revealing temperature-dependent slip system activation and the influence of solute atoms on flow behavior, which is crucial for high-temperature magnesium alloy applications.

Contribution

It provides new insights into the deformation mechanisms of CaMg₂ at elevated temperatures, especially regarding slip system activation and serrated yielding behavior.

Findings

Serrated flow decreases with temperature increase.

Solute atoms influence flow behavior in off-stoichiometric CaMg₂.

Deformation mechanisms vary across the 50-250°C range.

Abstract

Intermetallic phases can significantly improve the creep resistance of magnesium alloys, extending their use to higher temperatures. However, little is known about the deformation behaviour of these phases at application temperatures, which are commonly below their macroscopic brittle-to-ductile-transition temperature. In this study, we therefore investigate the activation of different slip systems of the CaMg$_2$ phase and the occurrence of serrated yielding in the temperature range from 50$^\circ$C to 250$^\circ$C. A decreasing amount of serrated flow with increasing temperature suggests that solute atoms govern the flow behaviour when the CaMg$_{2}$ phase is off-stoichiometric.