A study of cold ironing as a post-process for net-shape manufacture

Cold forming processes have the potential to enable net-shape components to be made. For net-shape with associated close tolerances to be achieved, a scientific understanding of the elastic distortions arising in the tooling is necessary. To become a useful process, cold ironing as a post-forging operation of warm forged gears needs a clear understanding of form errors due to die-elasticity and springback of component shape. The work described in this paper is aimed at gaining such an understanding. In order to simplify the analysis of cold ironing, a single tooth ironing die, instead of a whole gear die, has been designed and made. The effects of initial interference between die and single tooth in the process were studied experimentally and by FE simulation. The changes in geometrical profile, dimensions, and surface finish in the single tooth were observed. This study reveals the relationship between process variables and demonstrates that predicted dimensions can be achieved and surface finish greatly improved. (C) 2002 Elsevier Science Ltd. All rights reserved.