基于流线型凹模型腔的直齿圆柱齿轮冷挤压数值模拟分析

齿轮挤压属于体积成形，它是一个三维非稳态塑性成形过程，变形机制十分复杂。基于NURBS曲面构造流线型凹模型腔，用大变形刚塑性有限元数值模拟软件对圆柱直齿轮挤压过程进行了模拟。结果表明，采用流线型凹模型腔的连续性挤压成形，在改善角隅部分金属的充填性、减少变形突变以及提高变形分布均匀性等方面十分有效。这一结论可以作为齿轮挤压工艺设计的参考。

Numerical simulation analysis of cold extrusion for spur gear based on streamline cavity

Cold extrusion of gear is a 3D volume plastic but non-steady-status forming process, whose deformation mechanism is extremely complex. This paper constructs a streamline die cavity based on NURBS and simulates the extrusion process of spur gear in an application, in which large deformation rigid-plastic FEM is adopted. The results indicate that continuous extrusion utilizing streamline die cavity is effective in improving metal filling in corner, reducing deformation break and enhance the uniformity of deformation distribution. This conclusion can be adopted as a reference for process design of gear extrusion.