Coupled simulation of process-integrated powder coating by radial axial rolling of rings

Abstract

The process-integrated powder coating by radial axial rolling of rings represents a new hybrid production technique that combines the diameter increase of ringshaped work pieces with the application of functional outer layers [1]. The hot rolling of the ring is strongly influenced by a coupled temperature field since the forming resistance of the ring has to be kept under a certain level. The fact that the coating is produced by powder metallurgy brings up another problem: In conventional ring-rolling processes the infeed of the axial and the radial rollers in order to increase the ring’s diameter are controlled by the assumption of volume consistency [6]. But this is not true any more for a ring exhibiting a compressible layer. Thus attention has to be drawn to a different coupling scheme of the roller infeed with the current shape of the ring. The paper deals with the finite element (FE) modelling of this new process. A parameterized 2D model is used to examine the influence of several parameters on the residual porosity in the layer. Therefore different geometric parameters are examined as well as the influence of the roller and the ring geometry. It will be shown that the implementation of a PID control unit is essential to ensure the roundness of the final ring shape [5]. At the end the simulation results are illustrated.