Home Cyaniding Cyaniding Cyaniding is a fast and efficient case-hardening process that’s typically used on low-carbon steels. It introducing carbon and nitrogen into a solid ferrous alloy by holding above Ac1 in contact with molten cyanide or suitable composition. The cyanided alloy is usually quench hardened and then tempered to produce a case with a desired combination of hardness and toughness. < Glossary