Structure and properties of AZ31B magnesium alloy sheets processed by repeatedly unidirectional bending at different temperatures

Repeatedly unidirectional bending (RUB) was applied to the magnesium alloy sheet to improve the basal texture. The effect of RUB temperature on resulting structure and room temperature properties was investigated. The texture components of the sheet undergoing RUB at recovery temperature were similar to those of the sheet undergoing RUB at room temperature (RT). As the RUB temperature increased to above recrystallization temperature, the texture components became more disperse and the pyramidal components increased. With the increase of RUB temperature, the grain size near the surface of the sheets undergoing RUB tended to grow up. When the sheets were processed by RUB at medium-high temperature followed by annealing at 533 K, the yield strength and fracture elongation were lower than those of the cold rolled sheet; however, the Erichsen value was slightly higher than that of the cold rolled sheet. The sheet undergoing RUB at RT followed by annealing at 533 K represented the best mechanical properties.