带横向内筋特征构件外强旋压成形机理研究

Exploring Forming Mechanism of a Part with Transverse Inner Rib during Power Spinning

为了揭示带横向内筋特征构件外强旋成形机理,基于ABAQUS/Explicit平台建立了符合实际的带横向内筋构件外强旋成形三维有限元模型,分析了筋部充填特征及其金属流动规律。结果表明:工件筋部充填沿周向分布均匀,轴向分布较不均匀,其中筋部中区出现明显的表面凹陷,该凹陷是充筋中期轴向拉应力的减薄作用和充筋后期工件非筋部的弯曲靠模作用机制共同造成的;筋部成形前期,金属的径向流动大于轴向流动,筋部成形中、后期,金属的轴向流动大于径向流动。

In order to reveal the forming mechanism of a part with a transverse inner rib during power spinning, a 3D finite element model for the process was established based on ABAQUS/Explicit in this study. With this model, the rib characteristics and the metal flow rules during the filling process were researched. The results and their anal-ysis show preliminarily that：the filling of metal to the rib groove along the hoop direction is homogeneous while it is non-homogeneous along the tangential direction. Besides this, there is an obvious depression in the outer wall in the middle zone of the rib. The forming mechanism of this depression explored by us, we believe, consists of：（1） this depression results from the thinning effect due to axial tensile stress during the middle stage of rib filling and the closing to the mandrel as a result of the bending of the non-rib part of the workpiece at the end of rib filling;（2） as the filling process goes on, the flow of metal along the radial direction is larger than that along the tangential direc-tion in the earlier stage, while the former becomes smaller than the latter at the end of the filling process.