Tool steel is a type of carbon alloy steel that is well-matched for tool manufacturing, such as hand tools or machine dies. Its hardness, resistance to abrasion and ability to retain shape at increased temperatures are the key properties of this material.
Tool steel is typically used in a heat treated condition which provides increased hardness. Several grades have additional resistance to corrosion due to added chemical properties such as vanadium.
Also, with certain grades the manganese content is restricted in order to minimize the potential of cracking while water quenching. Other grades offer various methods other than water to quench the material, such as oil