Known for their low density and biocompatibility, magnesium alloys are ideal for lightweight applications and bio-implants. However, limited ductility and strength have hindered their widespread use. Carvalho and Figueiredo from the Federal University of Minas Gerais in Brazil have investigated the deformation mechanisms of ultrafine-grained magnesium alloys, involving grain boundary sliding (GBS).
Highlights
Ultrafine-grained Mg-Al-Zn alloy with a grain size of 140 nm was produced using high-pressure torsion.
The effect of grain size on hardness, flow stress, and strain rate sensitivity was investigated.
The critical role of GBS in the deformation of ultrafine-grained magnesium alloys was confirmed.
A transition between grain refinement hardening and softening was observed, along with increased strain rate sensitivity.
Comparisons with theoretical models revealed the close relationship between grain size and deformation mechanisms.
Fig. 1. Microstructure and grain size distribution of the HPT-processed Mg alloy.
Fig. 2. Flow stress as a function of strain rate at room temperature and 373 K for experiments, GBS creep, and Coble creep mechanism.
Authors
The authors of the paper is Amanda P. Carvalho and Prof. Roberto B. Figueiredo from Universidade Federal de Minas Gerais. Prof. Roberto B. Figueiredo is the corresponding author of this work.
This work was supported by the Conselho Nacional de Desenvolvimento Científico e Tecnológico and the Fundação de Amparo à Pesquisa do Estado de Minas Gerais.
A.P. Carvalho, R.B. Figueiredo, The contribution of grain boundary sliding to the deformation in an ultrafine-grained Mg–Al–Zn alloy, Journal of Materials Science (2023). https://doi.org/10.1007/s10853-023-08489-1
