AZ31镁合金轧制板材的两阶段气胀成形研究

研究了AZ31镁合金轧制板材在523 K, 0.3 MPa与623～673 K, 0.55～0.7 MPa下的两阶段气胀成形性能。结果表明:胀形件的厚向应变不均匀, 第二阶段变形的等效应力值明显小于第一阶段, 出现了软化现象。显微组织观察和表面形貌分析表明: 在第一阶段变形过程中, 由于动态再结晶的作用, 晶粒被显著细化, 从而得到了第二阶段变形所需的等轴细晶组织。在第二阶段变形过程中, 晶界滑移起主导作用, 并伴随有一定量的晶内滑移发生。

Research on Two-stage Gas Bulging Forming of a Rolled Magnesium Alloy AZ31

The Two-Stage gas bulging forming of a rolled magnesium alloy AZ31 under the conditions of 523 K, 0.3 MPa and 623 -673 K, 0.55 - 0.7 MPa, was investigated respectively. The wall thinknesses strains are different in a single gas bulging forming pan. The stress in the second-stage forming is much lower than that in the first-stage, and softening is observed. Optical microstructral observation and SEM observation show that in the first stage,the grain refinement after forming is obvious due to dynamic recrystallization and it is virtually beneficial to the second stage. During the second forming stage, grain boundary sliding functions mainly and accompanied with some inner-grain slide.