EN19
EN19 is a high-tensile alloy steel made with chromium and molybdenum. It’s well known for its excellent strength, toughness, and resistance to wear and fatigue. This makes it a reliable choice for parts that need to perform under high stress.
One of the key advantages of EN19 is its balanced mix of ductility, hardness, and machinability. It’s typically supplied in hardened and tempered, annealed, or normalized conditions, and can be further heat treated to fine-tune its mechanical properties. It also responds very well to surface hardening methods like induction hardening or nitriding, which can improve surface durability without weakening the inner core.
EN19 is widely used in demanding applications across industries like automotive, aerospace, oil & gas, and general engineering.
Applications
EN19 steel is used to manufacture gears and gear shafts due to its high tensile strength and wear resistance.
EN19 is ideal for crankshafts, camshafts, and axles in automotive and heavy machinery applications.
EN19 material is suitable for drive shafts and connecting rods, offering excellent toughness and fatigue resistance.
EN19 is commonly used in machine tool spindles and couplings for its strength and durability.
EN19 is preferred for high-strength bolts and fasteners that must withstand dynamic loads.
In the oil and gas industry, EN19 is applied in drill collars and tool joints for its ability to handle extreme stress.
Dealer
We are a leading dealer, supplier, stockist, and trader of Alloy Steel EN19, serving major industrial hubs and cities across India. We offer EN19 steel in various forms such as round bars, rods, and forged components, available in annealed, normalized, or hardened and tempered conditions to meet diverse engineering and manufacturing requirements.
Hardness
EN19 steel typically has a hardness of 179 to 217 Brinell Hardness (HB). When normalized, its hardness increases slightly, usually ranging from 200 to 250 HB.
EN19 can reach a hardness of 248 to 302 HB, depending on the specific heat treatment applied. When quenched and tempered, it can achieve up to 32 to 36 on the Rockwell C scale (HRC).
For components requiring a hard, wear-resistant surface, induction hardening can be applied, allowing surface hardness to reach 55 to 60 HRC, while maintaining a tough and ductile core.
Equivalent Grades
- AISI / SAE (USA): 4140
- DIN (Germany): 42CrMo4
- ASTM: A829 / AISI 4140
- JIS (Japan): SCM440
- ISO: 42CrMo4
- BS 970 (UK): 709M40
- UNI (Italy): 42CrMo4
- AFNOR (France): 42CD4
Heat Treatment
Annealing: Heat to 820–850°C, then slow furnace cool. Softens the steel for machining.
Normalizing: Heat to 870–900°C, then air cool. Refines grain and improves strength.
Hardening (Quenching): Heat to 840–870°C, quench in oil to increase hardness.
Tempering: Reheat to 540–680°C after quenching to reduce brittleness and improve toughness.
Nitriding: Heat to 500–530°C in nitrogen to harden the surface (up to 60–65 HRC).
Induction Hardening: Rapid surface hardening by induction heating, followed by quenching.
Hardening
Hardening Temperature: Heat to 840–870°C
Holding: Soak at this temperature to ensure uniform heating
Quenching Medium: Oil quenching is preferred to reduce cracking risk
Result: Steel becomes hard but brittle
Follow-up: Must be tempered to improve toughness and reduce brittleness
Welding
Preheating: Required at 200–300°C to reduce thermal shock and cracking risk
Welding Method: Preferably TIG, MIG, or manual arc welding with low-hydrogen electrodes
Interpass Temperature: Maintain between 200–300°C
Post-Weld Heat Treatment (PWHT): Stress relieving at 550–650°C is recommended to reduce residual stresses and brittleness
Filler Material: Use matching or compatible alloy filler rods (e.g., ER80S-B2)
Machinability
EN19 steel has good machinability, especially in the annealed or normalized condition. It responds well to conventional machining processes like turning, milling, drilling, and tapping.
In the annealed state, EN19 offers smooth cutting performance with minimal tool wear.
In the hardened and tempered condition, machining becomes more challenging and requires carbide tools, slower cutting speeds, and effective cooling.
Proper selection of cutting tools and use of coolants/lubricants are essential to maintain surface finish and tool life.
Physical Properties
| Property | Density | Melting Point | Thermal Conductivity | Specific Heat Capacity | Electrical Resistivity | Modulus of Elasticity | Poisson’s Ratio | Coefficient of Thermal Expansion |
|---|---|---|---|---|---|---|---|---|
| Value | 7.85 g/cm³ | ~1425 – 1510°C | ~42.6 W/m·K at 20°C | ~460 J/kg·K | ~0.24 µΩ·m at 20°C | ~205 GPa | ~0.27 – 0.30 | ~12.3 µm/m·°C (20–100°C) |
Chemical Properties
| Element | Carbon (C) | Manganese (Mn) | Silicon (Si) | Chromium (Cr) | Molybdenum (Mo) | Sulfur (S) | Phosphorus (P) |
|---|---|---|---|---|---|---|---|
| Content (%) | 0.36 – 0.44 | 0.60 – 0.90 | 0.10 – 0.35 | 0.90 – 1.50 | 0.15 – 0.30 | ≤ 0.035 | ≤ 0.035 |
| Function | Increases hardness and strength | Improves toughness and hardenability | Enhances strength and elasticity | Improves wear resistance and corrosion resistance | Increases strength and high-temperature performance | Impurity (kept low to maintain toughness) | Impurity (controlled to avoid brittleness) |
Chemical Composition
| Element | Carbon (C) | Silicon (Si) | Manganese (Mn) | Chromium (Cr) | Molybdenum (Mo) | Sulfur (S) | Phosphorus (P) |
|---|---|---|---|---|---|---|---|
| Composition (%) | 0.36 – 0.44 | 0.10 – 0.35 | 0.60 – 0.90 | 0.90 – 1.50 | 0.15 – 0.30 | ≤ 0.035 | ≤ 0.035 |