Standards Development

Scope

This European Standard defines the grades and the corresponding requirements for spheroidal graphite cast irons.

This European Standard specifies 3 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. The third group deals with the interconnected ferritic-pearlitic grades. This European Standard does not cover technical delivery conditions for iron castings (see EN 1559-1 [3] and EN 1559-3 [4]).

This European Standard does not cover:

— ausferritic spheroidal graphite cast irons which are specified in EN 1564 [5];

— low alloyed ferritic spheroidal graphite cast irons which are specified in EN 16124 [6];

— continuous cast iron bars which are specified in EN 16482 [7];

— austenitic cast irons which are specified in EN 13835 [8];

— spheroidal graphite cast irons used for pipes, fittings and their joints which are the subject of EN 545 [9], EN 598 [10] and EN 969 [11];

— the grades of spheroidal graphite cast irons as specified in EN 545 which are used for products such as industrial valves, non-industrial manually operated shut-off valves and flanges and their joints, which are the subject of the applicable European product standards.

Purpose

The introduction of a new spheroidal graphite cast iron with a matrix mainly consisting of interconnected pro-eutectoid ferrite and quenched pearlite obtained by performing an austempering like heat treatment of a ferritic low manganese ductile cast iron. This new microstructure can lead to improved mechanical properties, and other benefits, including good machinability, good low-temperature toughness and impact properties, and uniformity throughout the sections due to the absence of segregations (no alloy elements). , As-cast manufacturing is also simple as as-cast grades are common ferritic grades.