十字轴闭塞式单向温挤压工艺

Study of occlusive unidirectional warm extrusion for cross shaft

采用数值模拟与物理实验相结合的方法对十字轴的单向温挤压工艺进行研究。结果表明,成形过程中,锻件顶部存在5个流动死区,且枝杈入口处金属流动速度梯度导致流动沟槽的出现;进入圆角和飞边充填阶段,型腔内压急剧增加,(A_锻-A_筒)截面积差达到最大值,所需成形力、合模力均急剧增加。基于浮动凹模技术进行了模具设计和成形实验,改进连皮高度之后,所得锻件成形效果较好,表层金属流线清晰可见,不存在金属折叠、缺肉现象。

By using finite element（FE）simulation and physics experiment,the occlusive unidirectional warm extrusion of cross shaft is studied.The results show that five flow dead-zones exist at the top of the forging,and the presence of flow velocity gradient at the entrance of branches results in the emergence of flow groove.At the filling stage of the fillet and the flash,the pressure in the cavity increases dramatically,and the difference between the cross-sectional areas（Aforge-Atube）reaches its maximum.Finally,based on the technology of floating die,the design of molds and the experiment are conducted,and the cross shaft is successfully forged.