| 20090320971 | METHOD FOR MANUFACTURING SPHEROIDAL CAST IRON MECHANICAL COMPONENTS - A method for manufacturing mechanical components made of spheroidal cast iron, comprising the following steps: -providing a casting of a mechanical component made of cast iron having a structure which is at least partially ferritic and has a carbon content ranging from 2.5% to 4.0% and a silicon content ranging from 2.0% to 3.5%; -bringing the cast iron casting having an at least partially ferritic structure to a temperature for partial austenitizing which is higher than the lower limit austenitizing temperature (Ac1) and lower than the upper limit austenitizing temperature (Ac3) for a time required to obtain an at least partially austenitic structure; -performing a thermal treatment for isothermal hardening at a temperature ranging from 250° C. to 400° C. in order to obtain a matrix which has at least partially a pearlitic-ferritic or perferritic structure. | 12-31-2009 |
