Superior Shock Resistance of Magnesium and Magnesium–Aluminum Alloys with Cerium Addition

Abstract

This study investigates the shock response of forged and annealed commercially pure magnesium (Cp–Mg) and its cerium (Ce)-alloyed variants (Mg–0.5Ce and Mg–3Al–0.5Ce). Shock loading is performed using a conventional shock tube setup at two pressure levels along the forging direction (FD). Under low-pressure conditions, all materials deform without fracturing, with Cp–Mg exhibiting the highest deflection. However, at higher pressure, Cp–Mg discs fracture, displaying brittle cleavage, whereas Mg–0.5Ce and Mg–3Al–0.5Ce absorb impact energy without failure due to their superior strength–ductility balance. Among the Ce-alloyed variants, Mg–3Al–0.5Ce demonstrates slightly better shock resistance, exhibiting lower deflection and effective strain. Shock loading does not alter the grain size but results in a high density of predominantly extension twins that complements slip activity in all materials, particularly at higher pressures and in Cp–Mg. Post-shock analysis reveals the greatest reduction in basal texture intensity in Cp–Mg, while Mg–0.5Ce and Mg–3Al–0.5Ce show a moderate decrease. This reduction is attributed to slip and twinning, with Cp–Mg displaying the highest twinning activity. Local misorientation analysis indicates strain localization and stress concentrations at twin–matrix interfaces. Overall, Mg–0.5Ce and Mg–3Al–0.5Ce exhibit superior shock resistance compared to Cp–Mg, owing to their higher toughness, lower twin density, and increased non-basal slip activity.