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

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.