5160 hardened steel is a type of carbon steel commonly used in tool and weapon manufacturing due to its excellent edge-holding ability and durability. This type of steel undergoes a tempering process, in which it is heated to high temperatures and then immersed in water or oil to rapidly cool it. This creates a hard, strong crystalline structure that improves the steel's mechanical properties, such as strength and elasticity.
It is characterized by having a high resistance to deformation and its ability to maintain a sharp edge for a long time. It is also used in the manufacture of automotive parts and heavy machinery due to its high resistance to fatigue and fracture.