Cr12Mo1V1 high carbon high chromium cold work die steel

Cr12Mo1V1 is a high-carbon, high-chromium cold-work die steel belonging to the ledeburitic steel category; it features high hardenability, high hardening capacity, and high wear resistance.
 
The key characteristics of Cr12Mo1V1 include:
· High hardenability: Capable of achieving uniform hardening across the entire cross-section.
· High wear resistance: Maintains dimensional and shape stability under high loads.
· High-temperature oxidation resistance: Exhibits good resistance to oxidation at elevated temperatures.
· Corrosion resistance after quenching: Demonstrates good corrosion resistance following quenching and polishing.
· Minimal heat-treatment deformation: Maintains good dimensional stability during the heat treatment process.
 
Chemical composition of Cr12Mo1V1 mold steel:
· Carbon (C): 1.40% to 1.60%
· Silicon (Si): ≤ 0.60%
· Manganese (Mn): ≤ 0.60%
· Phosphorus (P): ≤ 0.030%
· Sulfur (S): ≤ 0.030%
· Chromium (Cr): 11.00% to 13.00%
· Molybdenum (Mo): 0.70% to 1.20%
· Vanadium (V): ≤ 1.10%
· Cobalt (Co): ≤ 1.00%
 
Physical properties of Cr12Mo1V1 mold steel:
· Modulus of elasticity: 207,000 MPa
· Specific heat capacity (Cp): 461 J/(kg·K)
· Critical temperatures: Ac1 ≈ 810°C, Acm ≈ 875°C, Ar1 ≈ 750°C, Arcm ≈ 695°C, Ms ≈ 190°C
· Linear expansion coefficient: 10.5 × 10⁻⁶/°C (20–100°C), 11.5 × 10⁻⁶/°C (20–200°C), 11.9 × 10⁻⁶/°C (20–300°C), 12.2 × 10⁻⁶/°C (20–400°C)
 
Heat treatment process for Cr12Mo1V1 steel:
· Stress-relief annealing: After rough machining, heat the workpiece to 600–650°C and hold for 2 hours; cool with the furnace to 500°C, then remove and air-cool.
· Quenching: Slowly heat the workpiece to 600°C and hold for 20 minutes for the first preheating stage; after the temperature equalizes, heat to 850°C and hold for 30 minutes for the second preheating stage; finally, heat to 1020–1040°C, hold for 25–40 minutes, then remove and air-cool.
 
· Tempering: Temper immediately after quenching; perform tempering at least twice, with a holding time of no less than 2 hours for each cycle. Gauges and high-precision molds should undergo cryogenic treatment (-70°C) and high-temperature tempering to minimize deformation; the high-temperature tempering range is 500–560°C, resulting in a hardness greater than 58 HRC.