Mold Steel 
1.2379 is a high-carbon, high-chromium cold-work tool steel characterised by its elevated carbon content (approximately 1.55%) and rich alloying elements including chromium (around 12%), molybdenum, and vanadium. Through optimised chemical composition and heat treatment processes, it achieves an exceptional balance between wear resistance, toughness, and dimensional stability, establishing itself as the “hardcore performer” in modern industrial wear-resistant applications.
| Equivalent grades | GB | DIN | AISI | JIS | BS | |||||
| Cr12Mo1V1 | 1.2379 | D2 | SKD11 | BD2 | ||||||
| Chemical Composition | C | Si | Mn | Cr | P | S | V | Mo | Other | |
| 1.50-1.60 | 0.10-0.40 | 0.15-0.45 | 11.50-12.50 | 0.03MAX | 0.03MAX | 0.90-1.10 | 0.60-0.80 | – | ||
| Available size | Round Bar | Diameter | Length | |||||||
| 16-800mm | 2000-6000mm | |||||||||
| Flat Bar | Thickness | Width | Length | |||||||
| 16-400mm | 200-800mm | 2000-6000mm | ||||||||
| Surface condition | Black surface/ Grinded/ Machined | |||||||||
| Annealed hardness | HB225MAX | |||||||||
| Characteristics | Very high resistance against abrasive and adhesive wear due to a high volume of hard carbides in the steel matrix moderate machinability, good dimensional stability, toughness and through harden ability | |||||||||
| Applications | Shear blades,Thread rolling dies,Drawing and bending tools Flanging and straightening rolls,Fine cutting tools Deep drawing tools,Plastic mould for abrasive polymers Cold extrusion dies,Drawing dies | |||||||||
| Heat treatment | Hardening Harden from a temperature of 1000-1040oC followed by oil, warm bath (500-550oC, cooling bath or air. Hardness after quenching is 62-64 HRC. Tempering Tempering temperature: 150-550oC Tempering Temperature (oC) vs. Hardness (HRC) | |||||||||
| 100°C | 200°C | 300°C | 400°C | 500°C | ||||||
| 63 | 61 | 58 | 58 | 59 | ||||||
| Mechanical properties | Density | 7.7[g/cm3] | ||||||||
| Thermal Conductivity | 20.20 W/(m/k) | |||||||||
| Specific heat capacity[J/g.K] | 0.46 | |||||||||
| Coefficient of Linear Thermal Expansion 10-6 oC-1 | ||||||||||
| 20-100°C | 20-200°C | 20-300°C | 20-400°C | 20-500°C | ||||||
| 9.8 | 11.7 | 12.1 | 12.8 | 12.9 | ||||||
Superior Wear Resistance: Its high-carbon, high-chromium core formulation generates abundant hard, wear-resistant chromium carbides upon quenching and tempering. This ensures your cutting edges remain sharper for longer, while mould cavities withstand greater abrasion. Significantly reducing downtime for replacements, it effectively boosts equipment utilisation.
Outstanding Toughness: Despite its exceptional hardness, 1.2379 steel retains excellent toughness through precise heat treatment control. This prevents brittle fracture or chipping under impact loads and localised stress concentrations, ensuring safe and stable operation in demanding conditions.
Superior Dimensional Stability: Through meticulously engineered quenching and multiple high-temperature tempering processes, residual austenite within 1.2379 steel undergoes complete transformation, resulting in a stable microstructure. This delivers exceptional resistance to deformation, ensuring precision moulds and cutting tools maintain dimensional accuracy during prolonged use or temperature fluctuations, thereby guaranteeing consistent product batches.
Good Quenchability: Benefiting from a rational alloying element composition, 1.2379 steel achieves a deep hardened layer. Even large-section components attain uniform hardness and properties, meeting the demands of large, complex moulds and components.
Machinability and polishability:Demonstrates excellent machinability in the annealed condition, facilitating the production of intricate geometries. Following appropriate heat treatment, surfaces can achieve exceptionally high finishes, meeting applications demanding superior surface quality.
