
AISI D3 cold work steel, also know as DIN 1.2080 (Werkstoff) and JIS SKD1, is a 12% chrome alloy steel. D3 cold work steel has very high wear resistance against abrasive and adhesive wear due to the high volume of hard carbides in the steel matrix, medium toughness, dimensionally stable, high compressive strength, not secondary hardenable. Type AISI D3 cold works tool steel is oil-quenched; though small sections can be gas quenched after austenitization using vacuum. As a result, tools made with type D3 cold work tool steel tend to be brittle during hardening. Type D2 tool steel is the most commonly used steel among the group D steels. The D3 cold work steels contain 1.5 to 2.35% of carbon and 12% of chromium.
AISI D3 alloy steel is heat treatable and will offer a hardness in the range 58-64 HRC. After heat treatment D3 tool steel is hard, durable and dense, and is immune from sinking in use. It offers a measure of corrosion resistance when polished. In general, the applications of AISI D3 tool steel resemble those of D2 tool steel but it should be remembered that alloy tool steel D3 has better wear resistance of the two steels and is preferred for such items as shear blades. Owing to its higher wear resistance, AISI / ASTM D3 cold work steel is slightly more difficult to grind than D2 steels.