A novel buckling-induced forming method is proposed to produce metal bellows. The tube billet is firstly treated by local heating and cooling, and the axial loading is applied on both ends of the tube, then the buckling occurs at the designated position and forms a convolution. In this paper, a forming apparatus is designed and developed to produce both discontinuous and continuous bellows of 304 stainless steel, and their characteristics are discussed respectively. Furthermore, the influences of process parameters and geometric parameters on the final convolution profile are deeply studied based on FEM analysis. The results suggest that the steel bellows fabricated by the presented buckling-induced forming method have a uniform shape and no obvious reduction of wall thickness. Meanwhile, the forming force required in the process is quite small.

提出了一种新型屈曲诱导成形方法来生产金属波纹管。管坯首先经过局部加热和冷却处理，在管的两端施加轴向载荷，然后在指定位置发生屈曲并形成卷绕。本文设计开发了一种成型设备，用于生产304不锈钢的不连续和连续波纹管，并分别讨论了它们的特点。此外，基于有限元分析深入研究了工艺参数和几何参数对最终卷积轮廓的影响。结果表明，采用所提出的屈曲诱导成形方法制造的钢波纹管形状均匀，壁厚没有明显减少。同时，该过程所需的成型力很小。