EN 1561 specifies the properties of unalloyed and low-alloyed grey cast irons used for castings, which have been manufactured in sand moulds or moulds with comparable thermal behaviour.
This standard specifies the characterizing properties of grey cast irons by either:
— the tensile strength of cast samples,
— if agreed by the manufacturer and the purchaser, the tensile strength of samples cut from a casting,
— the hardness determined on the castings or a cast-on knob.
EN 1561 specifies six grades of grey cast iron by a classification based on tensile strength determined on machined test pieces prepared from cast samples and six grades of grey cast iron by a classification based on Brinell hardness.