基于变摩擦系数的铝合金覆盖件冲压成形模拟

Numerical simulation of stamping of aluminum alloy hood Inner panel based on variable coefficient of friction

使用自主研发的摩擦系数测试设备,测试了不同压力条件下6016铝合金板材的摩擦系数曲线。基于动态显式有限元法,对铝合金发动机罩内板进行冲压成形模拟仿真,计算了成形后零件的FLD图、厚度云图和应力云图等。结果表明,在冲压成形过程中,板料的移动速度先快速增大后急剧降低,随冲压时间不断变化。与固定的摩擦系数值相比,采用变摩擦系数模型计算得到的开裂和起皱量略高。试验结果表明,采用变摩擦系数值的仿真结果能更精确预测零件的成形缺陷。

Using a self-developed tribosimulator,the coefficient of friction curve of 6016 aluminum alloy was measured under the conditions of different pressure.The explicit dynamic finite element method is adopted to conduct numerical simulation of stamping of aluminum alloy hood inner panel to calculate the FLD figure,thickness distribution and stress field distribution.The results showed that the movement speed of sheet presented a rapid rise-to-fall and changed with the time.Compared with the calculated results by a constant coefficient of friction values,the quantity of crack and wrinkle obtained by variable coefficient of friction values were slightly higher.The stamping experiments show that variable coefficient of friction values used for numerical simulation in stamping process can improve the accurate in calculation of defects.