铝合金弧面节点板冲压成形回弹特性研究

Springback Characteristics of Arched Aluminum Alloy Gusset Plate in Stamping Forming

板式节点是铝合金单层网壳中最为常用的节点形式之一,为了满足网壳曲面的造型要求,其节点板通常采用冲压成形的弧面板。回弹是节点板成形过程的主要缺陷,准确预测回弹量是保证加工精度的关键。为此基于ABAQUS/Explicit&Standard平台模拟了弧面节点板的冲压成形过程,并将节点板回弹量与实际加工数据进行对比,验证了有限元模型的有效性。对铝合金材料参数、冲压拱度、节点板厚度和半径、螺栓孔的布置和开孔面积对节点板回弹量的影响进行了参数分析。最后,基于理论推导得到了节点板回弹量的计算式,通过回归分析得到了计算式的系数,并将理论公式计算结果与数值分析结果进行对比,验证了拟合算式的准确性。

Gusset joint is one of the most common joint systems used in single-layer aluminum alloy reticulated shells.In order to meet the modeling requirements of curved shell surface,arched gusset plates formed by stamping are usually adopted.The springback phenomenon is the main defect in the forming process of arched gusset plate,and the accurate prediction of the springback value is the key to ensuring the machining accuracy.In this paper,the stamping forming process of the arched gusset plate was simulated by using the ABAQUS/Explicit&Standard,and the finite element model was validated by the comparison of its springback value with the date of a practical gusset plate.Subsequently,a parametric analysis was conducted to investigate the effects of the material property,the value of stamping camber,the thickness and radius of the gusset plate,as well as the arrangement and total area of the bolt holes on the springback value.Finally,the calculation equation to estimate the springback value was proposed by theoretical deviation,and the coefficients of the equation were obtained by regression analysis.The good agreement between the calculation results and the numerical analysis results indicated that the proposed formula was with sufficient accuracy.