ISO 1083:2018 defines the grades and the corresponding requirements for spheroidal graphite cast irons.This document specifies two groups of spheroidal graphite cast iron grades by a classification based on mechanical properties measured on machined test pieces prepared from cast samples. The first group deals mainly with ferritic to pearlitic grades. The second group deals with solid-solution strengthened ferritic grades.This document also gives an informative classification as a function of hardness.This document does not apply to the following:— spheroidal graphite cast irons used for pipes, fittings and accessories which are specified in accordance with ISO 2531 and ISO 7186;— highly alloyed (austenitic) spheroidal cast irons which are specified in accordance with ISO 2892;— ausferritic cast irons which are specified in accordance with ISO 17804.