金属板材无模渐进成形板厚变化仿真与实验研究
Experimental and Numerical Research on Thickness Variation of Dieless Sheet Metal Incremental Forming
李军超， 张 旭， 彭守桃
点击：4320次 下载：0次
作者单位：(重庆大学 材料科学与工程学院, 重庆 400044)
中文关键字：渐进成形； 无模； 数值模拟； 板厚变化
英文关键字：incremental forming; dieless; numerical simulation; thickness variation
中文摘要：板厚变化是板材渐进成形工艺涉及的主要问题，与成形角度、层间距等工艺参数密切相关。针对成形角度分别为45°和60°的方锥件，结合数值模拟和实验结果证明余弦定理可用于预测成形零件的板材厚度，但预测值较实际值偏大。运用无模渐进成形有限元模型，分析了工具头尺寸和层间距对板材厚度变化的影响，结果表明大的工具头尺寸和小的层间距有助于提高板厚的均匀化程度，不同的工具头尺寸虽然导致板厚均匀区域大小有所差别，但最终的板厚尺寸趋于一致，随着层间距的增大，余弦定理的预测误差增大。
英文摘要：Thickness variation, which is closely related to processing parameters including forming angel and step increment, is one of the main problems in sheet metal incremental forming. For two square pyramid parts whose forming angels are 45° and 60°, respectively, the numerical and experimental investigations show that cosine law can predict the thickness of forming parts, but the predictive value is slightly larger than the actual one. Then, utilizing the finite element model of dieless incremental forming, the effects of tool size and step increment on the thickness variation were analyzed. The results show that large tool size and small step increment contribute to the uniform of thickness distribution, the final thicknesses for different tool sizes are gradually to be the same, although the areas of plastic zone with uniform thickness may be different, and the predictive error by cosine law may be increased with the increase of step increment.