Abstract:

In this paper, a simplified 1/4 rotational symmetrical model is built with the aid of finite element software MSC. Marc, and the high-speed steel-ball spinning process of thin-wall copper tube with axial micro-grooves is simulated. Afterwards, the forming characteristics, as well as the distributions of the equivalent stress and strain and of the residual stress, is analyzed. The results show that the metal rebound occurring in the forming process may result in forming gaps at the tooth root, that both the equivalent and the three-direction stress and strain arrange in layers in the axial direction, that the equivalent stress on the exterior wall surface, which is greater than the yield stress of the material, leads to the emergence of copper scale and fracture, that the equivalent stress and strain as well as the residual stress at the groove bottom are larger than those at the tooth tip and those on the exterior wall surface, and that larger residual stress may result in material embrittlement and surface cracks.

Key words: axial micro-grooved copper tube, steel-ball spinning, forming characteristic, stress, strain, finite element analysis