# Microstructural Analysis of Hot-Compressed Mg-Nd-Zr-Ca Alloy with Low Rare-Earth Content

## TL;DR

This paper studies the microstructure of a low rare-earth magnesium alloy after hot compression, revealing how deformation and recrystallization mechanisms affect its properties.

## Contribution

The study identifies specific dynamic recrystallization mechanisms and microstructural evolution in a low-RE Mg-Nd-Zr-Ca alloy during hot compression.

## Key findings

- The equivalent strain distribution in compressed specimens is heterogeneous, with higher strain in the core.
- Necklace-like structures form after thermal compression, and CDRX, TDRX, and PSN are the primary DRX mechanisms.
- Mg41Nd5 and α-Zr phases increase dislocation density and promote cross-slip activation.

## Abstract

Microstructural analysis of hot-compressed magnesium alloys is crucial for understanding the plastic formability of magnesium alloys during thermo-mechanical processing. Thermal compression tests and finite element simulations were conducted on a low rare-earth (RE) Mg-1.8Nd-0.4Zr-0.3Ca alloy. Multiple microstructural characterization techniques were employed to analyze slip systems, twinning mechanisms, dynamic recrystallization (DRX), and precipitate phases in the hot-compressed alloy. The results demonstrated that the equivalent strain distribution within compressed specimens exhibits heterogeneity, with a larger equivalent strain in the core. After thermal compression, the original microscopic structure formed a necklace-like structure. The primary DRX mechanisms comprise continuous dynamic recrystallization (CDRX), twin-induced dynamic recrystallization (TDRX), and particle-stimulated nucleation (PSN). Pyramidal slip and recrystallization constitute primary contributors to peak texture weakening and tilting. Mg41Nd5 and α-Zr phases enhanced dislocation density by impeding dislocation motion and promoting cross-slip activation. Hot compression provided the necessary thermal activation energy and stress conditions for solute atom diffusion and clustering, triggering dynamic precipitation of Mg41Nd5 phases.