一种新的实体壳单元在板料成形中的应用

A new solid-shell element(MSSS) for sheet forming simulation

开发了一种新的实体壳MSSS单元,在厚向划分一层网格采用多点积分,精确获得了厚向应力应变分布;采取粘性沙漏控制算法,克服了零能模式。厚向多点积分求解内力以及应力应变的更新,使得MSSS单元表现出了极好的单元性能,可以准确描述板料成形回弹现象。基于FASTAMP板料成形模拟软件,论文给出了一个方板拉深成形算例,以及两个NUMISHEET国际标准考题回弹算例,并且与实验结果以及相关文献中的模拟结果做了比较。

A new solid-shell element （MSSS） with a single layer and multiple integration points through thickness developed in this work could obtain accurate distribution of stress and strain in thickness direction; Damping hourglass control method is requred in order to avoid the appearance of spurious deformation modes. Solution of internal force in thickness direction and updating of stress and strain using multiple integration points, make MSSS element show an excellent performance and could accurately describe springback phenomenon in sheet forming simulation. One deep-drawing example of a square box for forming and two NUMISHEET international benchmark examples for springback are carried out and the results are compared with experimental datas as well as referenced simulation results, based on sheet metal forming simulation system FASTAMP.