铝合金板材冲压成形极限虚拟预测

利用虚拟成形极限应变(FLD)试验,并根据虚拟试验过程中的“分叉失稳”和有限元后置处理过程中的“应变集中”现象,虚拟性地求解了铝合金板材的失稳极限应变。试验表明,虚拟FLD试验方法避免了采用塑性失稳准则及损伤断裂失稳准则时人为因素的影响,利用虚拟极限应变所拟合出的FLD曲线与实测FLD拟合曲线具有比较接近的几何图形,虚拟FLD试验可替代或部分替代实测FLD试验。

Virtual Predication of Stamping Formation Limitation of Aluminum Alloy Sheets

Through the virtual forming limitation deformation test and according to'branch destabilization'in virtual test and the'strain concentration'phenomenon in post processing of FEM,the destabilization limitation strain of aluminum alloy sheets is solved virtually.Tests indicate that the virtual FLD test method can avoid the effects of human factors in applications of the plastics instability criterion and the damage and breakdown instability criterion,the fitted FLD curve of the virtual FLD approaches to that of actually measured fitted FLD curve,therefore the virtual FLD test can be substitued wholly or partly for the actual FLD tests.