闭挤式精冲工艺及其成形规律

针对存在的低塑性和高厚度零件难以精冲成形问题,提出了闭挤式精冲的概念和工艺方法,并阐述了该工艺的过程、原理和特点;设计了该闭挤式精冲工艺实验模具并用该工艺在低塑性材料YL12上精冲出了φ15 mm、高13 mm的高尺寸精度和低粗糙度的圆柱形零件.最后分析了变形区材料的流动规律和产品品质与坯料的关系.结果表明:精冲件外表面的光亮带大小随外环填充率增大而增大;内表面比外表面容易形成100%光亮带;试件表面的光亮带大小还与坯料厚度和模具主、副凹模凹坑深度的匹配有较大关系.

Reach on process of closed extruding fine-blanking and material flowing rule

As for the existed problem that inductile parts with high thickness were hard to deform by fine-blanking, the concept and process of closed extruding fine-blanking were proposed, and the principles and characteristics of the process's course were described. The experiment die of closed extruding fine-blanking was designed. Using this process, cylindrical parts of 15 mm in diameter and 13 mm in height with highly dimensional precision and low degree of roughness were deformed on the basis of inductile material YL12. Finally, the flowing law and product quality of mate-rials in deformation zone, and the relationship between the die and billets were analysed. The results show that for the exterior surface of fine-blanking parts, the higher packing rate, the larger light-zone; the inner surface is easier to form whole light-zone than the exterior surface; and the size of the surface's light-zone is also largely related to the stock thickness and the match of the main and supplementary die's pitting depth