The 410 has good corrosion resistance in moderately corrosive environments, such as steam, fresh water, foodstuffs. It should not to be used in highly corrosive environments.
The 420 is the most widely used martensitic steel because, thanks to its carbon content, it is possible to achieve excellent mechanical values after quenching and tempering. The carbon content increases, going from 420A, to 420B up to 420C. They are used in pumps, moulds, tools and springs sector.
The 440C has a carbon content close to 1% and a chromium content higher than previous steels, which makes it usable, quenching and tempering, in bearings, diesel engines and surgical tools sector.
For those who require high machinability, the 430F is available, resulphurised steel and therefore suitable for chips that break easily during machining.