METHOD FOR MANUFACTURING MECHANICAL COMPONENTS MADE OF COMPACTED GRAPHITE IRON OR GRAY CAST IRON

摘要

A method for manufacturing mechanical components made of compacted graphite iron or gray cast iron, comprising the following steps: – providing a casting of a mechanical component made of gray cast iron or compacted graphite iron having at least 50% of ferritic structure and having a carbon content comprised between 2.5% and 4.0% and a silicon content comprised between 1.0% and 4.0%; – bringing said casting to a temperature that is higher than the lower austenitizing temperature (Ac1) and lower than the upper 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 comprised between 230°C and 400°C in order to obtain a matrix that has a substantially pearlitic-ferritic or perferritic structure.