基于响应面法的渐进成形参数优化

Parameter optimization of incremental sheet metal forming by response surface method

金属板材的可成形性是制约渐进成形技术发展的一大障碍,板材的可成形性可以通过零件侧壁厚度直观体现,过度减薄会造成制件的破裂。对工具头尺寸、轴向进给量、成形角和板材厚度对板材减薄率的影响进行了分析。利用拉丁方试验设计法进行数据采样,并对数据进行方差分析,得出试验参数对减薄率影响的主次顺序。结果表明,影响板材渐进成形减薄率的主要因素是成形角度、轴向进给量与工具头直径,次要因素是板材厚度。在此基础上采用响应面方法构建了减薄率的近似优化模型,并通过序列二次规划算法(SQP)对近似模型进行优化分析得到,当板厚为1.5 mm、工具头大小为17 mm、轴向进给量为0.85 mm时,板材厚度分布均匀,减薄率大小与理论数值接近。

Formability is an obstacle to the development of incremental sheet forming（ISF）.Formability of sheet metal can be estimated by the side wall thickness of parts,and excessive thinning will lead to the fracture of sheet metal.The influences of tool head size,axial feed,forming angle and sheet metal thickness on the thinning rate were investigated.The Latin square design of experiment was used for sampling of data,and the order of parameter influence on the thinning rate was obtained through variance analysis.The results show that forming angle,axial feed and tool head diameter are the main factors that affect the sheet metal thinning rate in the incremental sheet forming process.On the basis above,the approximate optimization model for thinning rate was set up by the response surface method and analyzed by sequential quadratic programming（SQP）.When the sheet metal thickness is 1.5 mm,tool head diameter is 17 mm and axial feed is 0.85 mm,the thickness distribution of sheet metal is regarded as uniformity,and thinning rate is consistent with the theoretic result.