Influence of magnesium on hydrogenated ScAl1−xMgx alloys: A theoretical study

► We investigate the effect of magnesium on stability of the ScAlMg hydrogenated alloys. ► We examine different microstructures for the ScAlMg hydrogenated alloys. ► By increasing the Mg content, the stability of ScAlMg hydrogenated alloys increases. ► The thermodynamics of the ScAlMg hydrogenated alloys is strongly influenced by the microstructure of the sample.