A billet is successively cold worked into a product such as a countershaft, an outer race for a constant-velocity joint, or the like by forming a chemically converted lubricating coating on a surface of the billet, forging the billet into an intermediate product at a temperature below a transformation...http://www.google.es/patents/US5007266?utm_source=gb-gplus-sharePatente US5007266 - Successive cold working process
