During stamping process, the material properties, process design parameters and production environments inevitably have variation and noisy factors, which possibly affect the sheet metal formability and the deformatio...During stamping process, the material properties, process design parameters and production environments inevitably have variation and noisy factors, which possibly affect the sheet metal formability and the deformation of the die structure.After gaining a success in applying sheet metal forming numerical simulation analysis to get the forming loads during stamping process, a methodology of die structure analysis based on sheet metal forming simulation was proposed and validated by experiments.Based on these results, the effect related with initial blank thickness, blank holder force, blank positioning error and die alignment error variations to a DP600 hyperbolic bottomed cup drawing die's forming loads(especially unbalanced loads), and deformation and stress was studied numerically.The influence level of these variations to the die's forming loads, deformation and stress was disclosed.The findings can guide die design, die tryout and process control for high-strength steel(HSS) stamping with increased forming load and decreased sheet metal formability.展开更多
基于J M Alexander提出的轴向载荷作用下薄壁管轴对称坍塌机构化模型,针对薄壁管无模内高压成形端部塑性皱曲的局部性特征,提出了一种“皱曲区-膨胀区-皱曲区”的管坯区划模型。通过将基于塑性失稳系数的薄壳塑性稳定性理论与能量准则...基于J M Alexander提出的轴向载荷作用下薄壁管轴对称坍塌机构化模型,针对薄壁管无模内高压成形端部塑性皱曲的局部性特征,提出了一种“皱曲区-膨胀区-皱曲区”的管坯区划模型。通过将基于塑性失稳系数的薄壳塑性稳定性理论与能量准则相结合,在系统势能极小条件下,建立起薄壁管无模内高压成形端部塑性皱曲临界载荷的理论计算方法。展开更多
基金the National Natural Science Founda-tion of China (No. 50475020)the Ford Motor Company University Research Program (No. 20054004R)
文摘During stamping process, the material properties, process design parameters and production environments inevitably have variation and noisy factors, which possibly affect the sheet metal formability and the deformation of the die structure.After gaining a success in applying sheet metal forming numerical simulation analysis to get the forming loads during stamping process, a methodology of die structure analysis based on sheet metal forming simulation was proposed and validated by experiments.Based on these results, the effect related with initial blank thickness, blank holder force, blank positioning error and die alignment error variations to a DP600 hyperbolic bottomed cup drawing die's forming loads(especially unbalanced loads), and deformation and stress was studied numerically.The influence level of these variations to the die's forming loads, deformation and stress was disclosed.The findings can guide die design, die tryout and process control for high-strength steel(HSS) stamping with increased forming load and decreased sheet metal formability.
文摘基于J M Alexander提出的轴向载荷作用下薄壁管轴对称坍塌机构化模型,针对薄壁管无模内高压成形端部塑性皱曲的局部性特征,提出了一种“皱曲区-膨胀区-皱曲区”的管坯区划模型。通过将基于塑性失稳系数的薄壳塑性稳定性理论与能量准则相结合,在系统势能极小条件下,建立起薄壁管无模内高压成形端部塑性皱曲临界载荷的理论计算方法。