ELEMENTO DI COMANDO AZIONABILE A CAMMA DI UNA TRASMISSIONEPER SISTEMI DI COMANDO IN MOTORI A COMBUSTIONE INTERNA

摘要

Arrangement for providing an enhanced wear-resistant contact region for a cast iron mechanical control element such as a rocker arm. The control element is cast in a desired shape. It is then preheated to a temperature between room temperature and the Ms temperature of the iron element (Ms temperature is a function of the carbon content of the iron) to adjust the total hardness of the iron element. A surface region of a cast iron control element, intended for forming the contact region, is partially melted and then cooled to create a hard ledeburitic structure which has a mixed crystal structure and is at least partly martensitic and has a mixed hardness of at least 670 Hv.