Simulation of residual stresses and their impact on geometrical accuracy in incremental sheet metal forming
Simulation of residual stresses and their impact on geometrical accuracy in incremental sheet metal forming
复制标题
DOI：
10.1002/pamm.201800302
复制
发表时间：
2018-12
期刊：
影响因子：
--
通讯作者：
F. Maqbool;M. Bambach
中科院分区：
文献类型：
--
作者：
F. Maqbool;M. Bambach
研究了单点渐进成形工艺参数对残余应力和几何精度的影响。在SPIF中，通过半球形工具的连续局部变形来形成金属板。在这方面，通过改变工艺参数，由铝合金渐进地形成锥形部件。从这些金字塔的侧壁上切下小条，测量并比较所得到的条的曲率。钻孔法用于测量残余应力状态。此外，基于残余应力对采用各向同性硬化规则和混合硬化规则的两种不同数值模型进行了校准。混合硬化模型预测的结果更好。该经验证的数值模型用于模拟修剪时的几何偏差。将来自数值模拟的修剪条带的所得曲率与实验条带的曲率进行比较。因此，所建立的模型可以用来精确地模拟残余应力，进而模拟SPIF后的修整几何形状。
The current study presents the influence of the process parameters on residual stresses and geometrical accuracy in single point incremental forming (SPIF). In SPIF, a sheet metal is formed by the continuous localized deformation of a hemispherical tool. In this regard, pyramidal parts from an aluminum alloy are incrementally formed by varying the process parameters. Small strips are cut from the side walls of these pyramids and the resulting curvature of the strips is measured and compared. The bore‐hole‐drilling method is used to measure the residual stress state. Further, two different numerical models employing isotropic and mixed hardening rules are calibrated based on the residual stresses. The model with mixed hardening predicts better results. This validated numerical model is used to simulate the geometric deviation upon trimming. The resulting curvature of the trimmed strips from the numerical simulations is compared to the curvature of the experimental strips. A good agreement is found. Hence, the developed model can be used to accurately simulate the residual stresses and in turn the trimmed geometry after SPIF.