Exploring Strong Spinning Formation Mechanisms of GH3030 Superalloy Tapered Rotary Part with Wall Thickness Gradient

Xuedao Shu,Ying Zhu,Zixuan Li,Yu Wang,Zewei Cen

doi:10.1051/jnwpu/20193740785

Abstract

In order to effectively control the deformation of tapered spinning parts with gradually changing wall thickness, the precise forming of such sheet metal casing parts can be realized. This paper uses experiments to establish the true stress-strain curve equations of GH3030 superalloy at normal temperature. Based on the equations, it establishes the finite element model of the strong spinning forming of a GH3030 superalloy tapered rotary part with wall thickness gradient. The equivalent stress field for the strong spinning forming is used to combine the finite element simulation with experiments. The strong spinning forming is simulated, and the distribution characteristics of the equivalent stress field and the equivalent strain field for the strong spinning forming are analyzed in some detail, and their distribution law is obtained. The strong spinning forming mechanisms for the GH3030 superalloy tapered rotary part with wall thickness gradient is clarified. The experimental and simulation results are verified with the conical flange plane degree.

Highlights

This paper uses experiments to es⁃ tablish the true stress⁃strain curve equations of GH3030 superalloy at normal temperature. It establishes the finite element model of the strong spinning forming of a GH3030 superalloy tapered rotary part with wall thickness gradient
The strong spinning forming is simulated, and the distribution characteristics of the equivalent stress field and the equivalent strain field for the strong spinning forming are analyzed in some detail, and their distribution law is obtained
The experimental and simulation results are verified with the conical flange plane degree

Summary

Introduction

将上述信息导入 SIMUFACT.FORMING 有限元软件前处理中,得到 GH3030 高温合金壁厚渐变锥形回转件强力旋压成形的有限元模型如图 2 所示。综上所述,应力在渐变的壁厚中流动是有梯度的,主要是由于壁厚在渐变过程中金属流动约束不均而造成不均匀,在各成形阶段中,工件内、外表面的等效应力沿零件轴向分层分布;越靠近旋轮作用区,等效应力越大,最大等效应力位于与旋轮直接接触的位置;越靠近尾顶块作用区,等效应力越小,最小等效应力位于尾顶块作用区。即应力在渐变壁厚工件中呈梯度分布是由工件受到尾顶块、旋轮和芯模的共同作用所决定,过大的应力最容易使工件壁厚减薄量最大的部位产生破裂。 4.2 等效塑性应变分布特征 III区外壁与内壁等效塑性应变的差值沿工件轴向从小端到大端逐渐减小,如图 9 所示。这是因为沿工件轴向从小端到大端,工件的壁厚逐渐增大,即壁厚减薄量逐渐减少,而壁厚减薄量越小,则外壁金属沿旋轮进给方向的流动速度减慢,导致外壁金属与内壁金属的流动速度差越来越小。在整个成形过程中,III区最能反映整个毛坯的塑性流动特征,因此本文仅对III区的金属塑性流动性规律进行阐述。工件成形结束时,III区包含了编号为 17 ~ 23 之间的采样点。 III区内、外表面的采样点在整个成形过程中的空间位置变化情况如图 12 所示。

Results

Conclusion