变压边力条件下铝合金板的成形窗口

在由塑性成形理论和能量法分别建立的临界破裂和临界起皱压边力模型基础上,构建了变压边力情况下汽车用铝合金板的成形窗口,并分析了拉深比、材料参数和模具参数对成形窗口的影响规律.对比实验表明:在整个有效压边力范围内,数学模型构建的成形窗口能够与实验相吻合,且铝合金6111-T4和5052-O的成形窗口明显小于钢板st14的.而影响因素分析显示:随着拉深比降低、厚向异性系数(r)增加和凹模圆角半径(Rdp)增大,成形窗口明显扩大;n值增加,成形窗口虽然有所扩大,但是效果并不明显.

Formability window of aluminium alloy sheet at variable blank-holder force

Based on the variable blank-holder force(VBHF) models of critical fracture and critical wrinkling derived respectively from plastic deformation theory and energy method, the formability windows of automotive aluminium alloy sheets at VBHF were established, and the effect of drawing ratio, material parameters and die profile radius on formability window were analyzed. The comparison results show that the above formability windows are in agreement with the experiments in the range of effective blank-holder force, and the formability windows aluminium alloy 6111-T4 and 5052-O are less than that steel st14. The influencing factor analysis shows that the formability window obviously expands with the decreasing of the drawing ratio and the increasing of the normal anisotropical coefficient r-value and the die profile radius, but the effect of the hardening exponent n-value on formability window is not obvious.