1.2379
1.2379 is a high-carbon, high-chromium cold work tool steel, often regarded as the German equivalent of the popular D2 grade. It is widely used for applications requiring high wear resistance, hardness, and good dimensional stability after heat treatment.
This steel features approximately 12% chromium, which provides good corrosion resistance for a tool steel, along with excellent toughness and strength. Its wear resistance makes it suitable for cutting, forming, and blanking tools that undergo abrasive stresses at room temperatures.
1.2379 steel is typically air-hardened, meaning it achieves high hardness after cooling in air rather than oil or water, reducing the risk of distortion. It responds well to heat treatment and surface hardening processes like nitriding or induction hardening for enhanced durability.
Applications
Blanking and Forming Dies – Widely used in high-volume metal stamping and forming operations.
Shear Blades – Ideal for cutting and shearing tasks due to excellent wear resistance.
Cutting Tools – Used for making durable cutting tools that retain sharpness under stress.
Cold Extrusion Tooling – Maintains dimensional stability and wear resistance during extrusion processes.
Punches and Dies – Common in metalworking industries for precise and durable tooling.
Slitting Knives – Used for cutting sheet metals and strips with abrasive edges.
Wire Drawing Dies – Suitable for applications requiring resistance to wear and abrasion.
Plastic Molds – Utilized where wear resistance and dimensional stability are needed.
Roller Dies – Applied in rolling operations with high wear exposure.
Industrial Knives – Used in food processing, paper, and textile industries.
Dealer
We are a trusted dealer, stockist, and supplier of 1.2379 Cold Work Steel, offering premium quality steel for various industrial applications. Our inventory includes round bars, flat bars, plates, and custom sizes to meet diverse customer requirements.
Serving sectors like tool & die manufacturing, automotive, metalworking, and engineering, we ensure prompt delivery and consistent material quality. Our 1.2379 steel is sourced from reputable mills and comes with full material test certificates for assured performance.
Hardness
Annealed Condition:
Typically around 200–240 HB (Brinell Hardness), making it easier to machine.
Hardened Condition:
After heat treatment, 1.2379 steel can achieve hardness levels of 58 to 62 HRC (Rockwell Hardness), providing excellent wear resistance.
Tempering:
Tempering temperature influences the balance between hardness and toughness. Higher tempering reduces hardness slightly but improves toughness and dimensional stability.
Equivalent Grades
- DIN (Germany): – 1.2379
- AISI/SAE (USA): – D2
- BS (United Kingdom): – BD2
- JIS (Japan): – SKD11
- AFNOR (France): – Z160CDV12
- UNI (Italy): – X160CrMoV12
- UNI (Italy): – X160CrMoV12
Heat Treatment
Annealing:
Heat to 780–820°C and soak until uniform temperature is achieved.
Cool slowly in the furnace to soften the steel and improve machinability.
Hardening (Austenitizing):
Heat to 1000–1020°C to fully austenitize the steel.
Hold at temperature for sufficient time based on section size.
Quench in air or oil (air quenching preferred to reduce distortion).
Tempering:
Temper immediately after hardening to reduce brittleness.
Tempering temperature typically ranges between 150–550°C, depending on the desired hardness and toughness.
Double tempering is recommended to improve dimensional stability.
Stress Relieving (Optional):
After rough machining, heat to 600–650°C and hold for 1–2 hours, then air cool.
Helps relieve internal stresses prior to final hardening.
Hardening
Preheating:
Heat the steel gradually in two stages to reduce thermal stress:
• First stage: 450–500°C
• Second stage: 800–850°C
Austenitizing (Hardening Temperature):
Heat the steel to 1000–1020°C
Hold until fully austenitized, typically 20–30 minutes depending on part size.
Quenching:
Quench in air (preferred) or oil to transform the microstructure to hard martensite.
Air quenching minimizes distortion and cracking risks.
Tempering:
Temper immediately after quenching to reduce brittleness.
Temper between 150–550°C depending on desired hardness and toughness.
Double tempering is recommended for dimensional stability.
Welding
Preheating:
Preheat the material to 250–400°C to reduce thermal shock and minimize cracking.
Use Suitable Filler Metal
Use high-alloy filler rods designed for high-carbon, high-chromium steels.
Welding Process:
Prefer low-heat input processes such as TIG (GTAW) or MIG (GMAW) for better control.
Keep interpass temperatures controlled and weld quickly.
Post-Weld Heat Treatment (PWHT):
Perform stress relieving by tempering at around 550–600°C immediately after welding to reduce residual stresses.
Avoid Welding Hardened Steel:
If possible, anneal the steel before welding to reduce brittleness.
Machinability
Machinability Rating:
About 40–50% relative to free-machining steels, meaning it is tougher and requires more careful machining.
Tooling Recommendations:
Use carbide or ceramic cutting tools for best performance.
High-Speed Steel (HSS) tools may be used but tend to wear quickly.
Ensure a rigid setup to minimize vibration and tool wear.
Cooling & Lubrication:
Use ample oil-based coolant to reduce heat buildup and improve tool life.
Machining State:
Machine in the annealed condition (around 200 HB) for easier cutting.
Final finishing on hardened parts is often done by grinding or EDM.
Physical Properties
| Property | Value |
|---|---|
| Density | ~7.7–7.8 g/cm³ |
| Melting Point | ~1420–1460 °C |
| Modulus of Elasticity | ~210 GPa |
| Thermal Conductivity | ~20–25 W/m·K (at room temperature) |
| Specific Heat Capacity | ~460 J/kg·K |
| Electrical Resistivity | ~0.65 µΩ·m |
| Hardness (Annealed) | ~200–220 HB |
| Hardness (Hardened) | ~58–62 HRC |
Chemical Properties
| Property | Value |
|---|---|
| Wear Resistance | Very high, due to high carbon and chromium content |
| Toughness | Moderate – lower than shock-resistant steels but suitable for cold work tooling |
| Hardenability | Excellent – responds well to oil or air quenching |
| Corrosion Resistance | Moderate – better than plain carbon steels due to high chromium (~12%) |
| Dimensional Stability | Good – maintains size well after heat treatment |
| Tempering Resistance | Strong – retains hardness at elevated temperatures |
Chemical Composition
| Element | Carbon (C) | Chromium (Cr) | Molybdenum (Mo) | Vanadium (V) | Manganese (Mn) | Silicon (Si) | Phosphorus (P) | Sulfur (S) |
|---|---|---|---|---|---|---|---|---|
| Percentage (%) | 1.50 – 1.60 | 11.00 – 13.00 | 0.70 – 1.00 | 0.80 – 1.20 | 0.20 – 0.60 | 0.10 – 0.60 | ≤ 0.030 | ≤ 0.030 |