D2 steel is an alloy of iron, carbon and a small amount of other elements. D2 steel can be used to manufacture cold working dies with large cross-sections, complex shapes, high impact forces and high wear resistance.

D2 steel is a high wear-resistant, micro-deformation cold working die steel, wind-hardened tool steel, with a carbon content of up to 1.5%, a chromium content of up to 11.5%, and a hardness of up to 60HRC after heat treatment. D2 steel, such as silicon steel sheet punching dies, cold cutting scissors, trimming dies, etc.

Chemical composition
Carbon C: 1.40～1.6
Silicon Si: ≤0.60
Manganese Mn: ≤0.60
Sulfur S: ≤0.030
Phosphorus P: ≤0.030
Chromium Cr: 11.50～13.00
Nickel Ni: allowable residual content ≤0.25
Copper Cu: allowable residual content ≤0.30
Vanadium V: ≤1.00
Molybdenum Mo: 0.70～1.20

Features
High wear resistance, vacuum heat treatment to HRC60°-62°, excellent processing performance.

Heat treatment process
Stress relief annealing: After rough machining, heat the workpiece to 600~650℃, keep warm for 2h, cool to 500℃ with the furnace, and air cool out of the furnace.
Quenching: The workpiece is slowly heated to 600℃, kept warm for 20min for the first preheating, and then heated to 850℃ after equalization, and then kept warm for 30min for the second preheating, and finally heated to 1020~1040℃, kept warm for 25~40min, and air cooled out of the furnace.
Tempering: Temper immediately after quenching, and temper at least twice, each time holding time is not less than 2h
Note: Temper in time after quenching to prevent cracking and surface decarburization. Gauges and high-precision molds should be cryogenically treated (-70℃) and tempered at high temperature to reduce workpiece deformation. High-temperature tempering temperature is 500~560℃, and hardness is greater than 58HRC. Hardness: Annealing, ≤255HB, indentation diameter ≥3.8mm; quenching, ≥59HRC

Heat treatment specifications
Quenching, preheating at 820±15℃, heating at 1000±6℃ (salt bath) or 1010±6℃ (furnace controlled atmosphere), insulation for 10~20min, air cooling, tempering at 200±6℃.