Taylor simulation of cyclic textures at the surface of drawn wires using a simple flow field model

The deformation textures which develop during wire drawing at the surface of pearlitic carbon steel wires were simulated by means of the Taylor theory. These surface textures are so-called "cyclic textures", which do not have a full rotational symmetry such as the fibre textures found in the centre of drawn wires. This effect was believed to be caused by the more complex material flow which exists near the surface in comparison with the centre. The total plastic deformation undergone by a volume element of the material during passage through the plastic zone near the surface was split up into a large number of small deformation increments. Each of these was described by a different displacement gradient tensor. These tensors were fed to the Taylor program. In order to obtain this strain history it was necessary to use a simplified model for the flow field inside the wire drawing die. This model was analysed by means of techniques taken from the viscoplasticity theory. An example of the cyclic textures in the ferrite phase predicted by this method is given. The example is specific for pearlitic, high C steel; a special variant of the Taylor model was used. The result shown agrees qualitatively with a cyclic texture observed by other authors near the surface (but not at the surface) of a drawn wire.