Wrinkling behavior of magnesium alloy tube in warm hydroforming
来源期刊：中国有色金属学报(英文版)2010年第7期
论文作者：汤泽军 刘钢 何祝斌 苑世剑
文章页码：1288 - 1293
Key words：warm hydroforming; magnesium alloy tube; wrinkle; internal pressure; AZ31B magnesium alloy
Abstract: In tube hydroforming with axial feeding, under the effect of coupled internal pressure and axial stress, wrinkles often occur and affect the forming results. Wrinkling behavior of an AZ31B magnesium alloy tube was experimentally investigated with different loading paths at different temperatures. Features of wrinkles, including shape, radius and width, were acquired from the experiments, as well as the thickness distribution. Numerical simulations were carried out to reveal the stress state during warm hydroforming, and then the strain history of material at the top and bottom of the wrinkles were analyzed according to the stress tracks and yielding ellipse. Finally, effects of loading paths on expansion ratio limit of warm hydroforming were analyzed. It is verified that at a certain temperature, expansion ratio limit can be increased obviously by applying a proper loading path and realizing enough axial feeding.
