Plane Strain Bifurcation Behaviour of Thick Circular Tubes Subjected to Uniform Drawing at External Surface

Abstract

This paper deals with the nonaxisymmetric bifurcation of incompressible thick-walled circular tubes subjected to drawing at the outer surface under the plane strain condition. The influence of the yield stress, the hardening rate and the shape of the tubes upon the bifurcation behaviour is investigated. The results show that the short wavelength surface mode is the first bifurcation mode encountered in the deformation history for thick tubes with high work hardening rate and conversely, the long wavelength mode is that for thin tubes with low work hardening rate. The yield stress does not affect the bifurcation behaviour. The surface mode extends to the deep part of the tube as the workhardening rate decreases.