Microstructure, bending behavior and texture evolution of AZ31B magnesium alloy bending products processed by staggered extrusion (SE)

摘要

Staggered extrusion (SE) is a new process to realize an integrative process, combines an extrusion process and a bending process. The SE process can solve bottlenecks of traditional bending products, such as long processes, poor flexibility in manufacturing processes. The staggered distance (h) of the stem is a key parameter to determine bending characteristics and quality of the bending products. The effect of h on the SE process was investigated in this paper. With the increase of h, the extrusion load peak appears delay and decreases obviously. The value of h is directly proportional to the maximum bending height of bending products and inversely proportional to the bending radius. After the SE process, the AZ31 magnesium alloy grains were refined obviously and dynamic recrystallized structures were evenly distributed in bending products. The AZ31 Mg bending products were produced strong extrusion fiber texture by SE process, and texture intensity was higher at {0001} < 11 - 20 > and {10 - 11} < 11 - 23 >. The appearance of twins in AZ31 magnesium alloy bending products had a remarkable impact on the occurrence of dynamic recrystallization (DRX) and texture evolution. The SE process was investigated by technological experiments and microstructure deformation, which provided an important vital scientific basis for further application.