基于凹模压边区摩擦学性能的冲压仿真分析

通过改善凹模压边区摩擦学性能以提高冲压成形件质量,分别利用YLP-20型激光加工系统和多弧离子镀沉积设备在试样表面制备三角形微织构和TiN薄膜,采用UMT-3摩擦磨损试验机开展摩擦学性能试验;通过Dynaform软件建立有限元模型,以凹模压边区为研究对象,根据试验所得摩擦因数对冲压过程进行仿真分析。结果表明:镀膜和织构两种表面处理技术均能降低凹模压边区与板料间的摩擦因数,且先织构后镀膜技术具有最佳减摩效果;板料的减薄率随摩擦因数的减小而降低,增厚率则相反,并在摩擦因数减小到0.150后板料厚度变化趋于稳定;增大压边力会导致板料减薄率增加,减小凹模压边区与板料间的摩擦因数可抑制这一负面效果;将表面织构和镀膜技术应用于凹模压边区改善板料成形性能是可行的。

Stamping Simulation Analysis Based on Tribological Properties of Die-binder Area

To increase the stamping formability of sheet metal by improving the tribological properties of the die-binder area, an YLP-20 laser process system and a multi-arc ion deposition system were used to prepare triangular micro-textures and TiN coating, respectively. The tribological test was conducted by a UMT-3 pin-on-disk tribometer. The die-binder area was selected as the research subject, and the finite element model was established using Dynaform software. The stamping forming process was simulated according to the friction coefficient obtained from the above experiments. The results show that the laser surface texture technology and the coating technology can both reduce the friction coefficient between the die-binder area and the sheet metal. The texturing/coating technology has the best friction reducing effect. The thinning rate of the sheet metal decreases with the decreasing of the friction coefficient, while the thickening rate of the sheet metal increases. The change of the sheet metal thickness tends to be stable when the friction coefficient is lower than 0.150. The increase of die-binder force leads to the increase of the thinning rate. This negative effect can be controlled by reducing the friction coefficient between the die-binder area and the sheet metal. It is feasible to improve the stamping formability of the sheet metal by applying the surface texture and coating technology to the die-binder area.