Alloy steel 42CrMo4 (1.7225) for CNC machining

Highly loaded shafts, axles, gears, tooling.

Family

Steel

Density

7.85 g/cm³

Machinability

difficult (2/5)

Relative cutting speed

about 20% of aluminium 6082

Indicative price

€3 per kg

What to know

Usually bought quenched and tempered. Strong and tough, but slower to machine than C45.

Design tips

Carbon steels rust. Specify a coating such as zinc plating, black oxide or paint, and remember coatings add thickness.

Cheaper alternative

Carbon steel C45 (1.0503): If the part is not highly loaded or impact loaded, C45 is cheaper and quicker to machine.