D2 steel is a high-carbon, high-chromium tool steel that is commonly used in knives and other cutting tools. It is also known by other names such as SKD11, 1.2379, SLD, and Sverker 21. D2 steel has high wear and abrasion-resistant properties, and it is heat-treatable. It can offer a hardness in the range of 55-62 HRC and is machinable in the annealed condition. D2 steel shows little distortion on correct hardening. Its high chromium content gives it mild corrosion-resisting properties in the hardened condition. D2 steel is typically bought to meet chemistry requirements rather than physical requirements, so physical properties are generally not provided unless requested prior to production.

Typical applications for D2 steel include stamping or forming dies, punches, forming rolls, knives, slitters, shear blades, tools, and scrap choppers. D2 steel is a popular choice among knife makers due to its excellent edge retention and toughness combination. It is also used in industrial applications such as die-cutting and forming.

D2 steel is a deep hardening steel that can achieve a high hardness with high compressive strength after hardening. It has excellent dimensional stability in hardening, which makes it a quality through-hardening steel with good retention to tempering. D2 has good through-hardening properties and maintains good stability during heat treatment. It can also provide a measure of corrosion resistance when polished.

In summary, D2 steel is a high-carbon, high-chromium tool steel that is commonly used in knives and other cutting tools due to its high wear and abrasion-resistant properties, excellent edge retention, and toughness combination. It is also used in industrial applications such as die-cutting and forming. D2 steel is heat-treatable and can achieve a high hardness with high compressive strength after hardening.