EN36
EN36 Alloy Steel as Ultra-Hard Case with a Tough Core.It is a nickel-chromium case-hardening alloy steel, widely recognized for its ability to develop an extremely hard, wear-resistant surface while maintaining a strong, tough core. This makes it ideal for components that need to withstand continuous friction, impact, and stress over a long service life.
EN36 offers exceptional core toughness, even after heat treatment. When carburized and hardened, it achieves surface hardness levels of up to 60–62 HRC, making it perfect for applications like gears, crankshafts, camshafts, and heavy-duty automotive or aerospace components.
EN36 also has good machinability in the annealed state and responds well to carburizing, hardening, and tempering processes. Its mechanical strength and wear resistance make it suitable for high-performance and safety-critical parts.
Applications
Automotive Gears – Ideal for high-load transmission and differential gears.
Crankshafts and Camshafts – Withstands continuous rotation and high stress.
Heavy-Duty Shafts and Spindles – Used in industrial and power transmission equipment.
Pinions and Axles – Handles impact, torque, and wear in rotating machinery.
Aerospace Components – Suitable for parts requiring wear resistance and structural integrity.
Bearings and Bushings – Offers excellent surface durability for moving contact points.
Machine Tool Parts – Used in parts exposed to sliding and impact forces.
Dealer
We are a reliable dealer, supplier, and stockist of premium-grade EN36 alloy steel, serving a wide range of industries including automotive, aerospace, heavy engineering, and power transmission.
We offer EN36 in various forms such as round bars, flats, and custom-cut sizes, with assured quality, test certification, and competitive pricing. Our materials are suitable for carburizing and case-hardening applications, delivering a hard surface with a tough, wear-resistant core.
With our well-maintained inventory and strong supply network, we ensure on-time delivery, technical support, and material traceability to meet your project requirements.
Hardness
1. Annealed Condition:
Hardness is typically around 220–250 HB (Brinell Hardness)
Soft enough for easy machining before heat treatment
2. After Carburizing and Hardening:
Surface hardness can reach up to 60–62 HRC (Rockwell Hardness)
Provides excellent wear resistance for high-load and high-friction parts
3. Core Hardness (After Treatment):
Around 28–32 HRC, depending on section size and heat treatment
Maintains impact resistance and prevents brittleness
Equivalent Grades
- AISI / SAE (USA) 3310 or 9310 (closest equivalents)
- DIN (Germany) 17NiCrMo6 or 1.6565
- BS (UK - Old) 655M17
- UNI (Italy) 16NiCrMo13
- AFNOR (France) 16NCD13
- JIS (Japan) SNCM220 (comparable)
Heat Treatment
1. Carburizing:
Heat the steel to 880–930°C in a carbon-rich environment.
Hold at temperature long enough to allow deep carbon penetration (especially for thick sections).
Purpose: To enrich the outer layer with carbon for surface hardness.
2. Slow Cooling or Direct Quenching:
After carburizing, either cool slowly or quench directly, depending on the process and part size.
3. Hardening (Quenching):
Reheat to 780–820°C, then quench in oil or water.
Purpose: To harden the carburized surface while preserving core ductility.
4. Tempering:
Temper at 150–200°C after quenching.
Purpose: To relieve internal stress and slightly reduce brittleness, while maintaining high surface hardness.
Hardening
1. Carburizing:
Heat the steel to 880–930°C in a carbon-rich environment (solid, liquid, or gas).
Hold at this temperature long enough to allow deep carbon diffusion into the surface layer.
2. Reheating for Hardening:
After carburizing, reheat the part to 780–820°C to prepare for quenching.
Ensures uniform temperature across the carburized layer.
3. Quenching:
Quench in oil or water depending on section size and desired hardness.
Rapid cooling hardens the carburized surface to a high Rockwell value.
4. Tempering:
Temper the quenched part at 150–200°C.
This step reduces brittleness and internal stress while retaining surface hardness.
Welding
1. Weld Only in Annealed Condition:
EN36 should be welded before carburizing and hardening.
Avoid welding after case hardening, as it can cause cracking due to the brittle surface.
2. Preheating:
Preheat the material to 250–350°C before welding.
This reduces thermal shock and helps avoid weld cracking.
3. Use Low-Hydrogen Electrodes:
Use low-hydrogen welding rods or filler wires (e.g., E7018).
This minimizes the risk of hydrogen-induced cracking.
4. Controlled Heat Input:
Use short, controlled weld passes and maintain interpass temperatures to avoid overheating the surrounding material.
5. Post-Weld Heat Treatment (PWHT):
After welding, slow cool the material, then perform stress relieving at around 600–650°C.
If required, follow up with carburizing, hardening, and tempering again to restore properties.
Machinability
1. Annealed Condition:
In the annealed state, EN36 is easier to machine.
Cutting tools last longer, and surface finishes are smoother.
Recommended for all machining operations (turning, drilling, milling) before heat treatment.
2. After Carburizing or Hardening:
Once carburized and hardened, the steel becomes very hard and difficult to machine.
Only grinding or finish machining with specialized tools (e.g., carbide or ceramic inserts) is possible.
Surface hardness may reach 60–62 HRC, requiring precision equipment.
3. Coolants and Speeds:
Use appropriate coolants and moderate speeds to avoid tool wear.
Slower feeds with proper lubrication are recommended for extended tool life.
Physical Properties
| Property | Value |
|---|---|
| Density | 7.85 g/cm³ |
| Melting Point | ~1425–1460°C |
| Modulus of Elasticity | ~205 GPa |
| Thermal Conductivity | ~46 W/m·K |
| Specific Heat Capacity | ~460 J/kg·K |
| Electrical Resistivity | ~0.45 µΩ·m |
| Coefficient of Thermal Expansion | ~11.8 × 10⁻⁶ /°C (20–100°C) |
Chemical Properties
| Property | Value |
|---|---|
| Corrosion Resistance | Moderate; improves slightly with heat treatment and surface coating |
| Hardness | 220–250 HB (annealed); up to 60–62 HRC (after case hardening) |
| Tensile Strength | High; typically 850–1000 MPa (after treatment) |
| Toughness | Excellent core toughness due to high nickel content |
| Wear Resistance | Very high after case hardening (ideal for frictional components) |
| Heat Resistance | Stable mechanical properties up to ~400°C |
Chemical Composition
| Element | Carbon (C) | Silicon (Si) | Manganese (Mn) | Nickel (Ni) | Chromium (Cr) | Molybdenum (Mo) | Sulfur (S) | Phosphorus (P) |
|---|---|---|---|---|---|---|---|---|
| Percentage (%) | 0.10 – 0.20 | 0.10 – 0.35 | 0.45 – 0.70 | 3.00 – 3.75 | 0.60 – 1.10 | 0.08 – 0.15 | ≤ 0.035 (typically kept low) | ≤ 0.035 (typically kept low) |