When it comes to medium carbon high tensile alloy steels, few grades enjoy as much widespread use as EN19, also known by its equivalents like AISI 4140, 42CrMo4, and 708M40. However, buyers and engineers often encounter EN19 in multiple variants — EN19A, EN19B, and EN19C — especially in the Indian market where BS 970-1955 designations are still prevalent.
In this guide, Steelmet Industries explains the differences between these EN19 variants — including their chemical composition, mechanical properties, and suitability for different applications — to help you make an informed selection.
🧪 Chemical Composition Comparison (Typical Values)
| Element | EN19 | EN19A | EN19B | EN19C |
|---|---|---|---|---|
| Carbon (C) | 0.35–0.45% | 0.35–0.45% | 0.38–0.45% | 0.40–0.50% |
| Manganese (Mn) | 0.60–0.90% | 0.50–0.80% | 0.60–0.90% | 0.50–0.90% |
| Chromium (Cr) | 0.90–1.20% | 0.90–1.20% | 0.90–1.20% | 0.90–1.20% |
| Molybdenum (Mo) | 0.15–0.35% | 0.15–0.35% | 0.15–0.35% | 0.15–0.35% |
| Sulphur (S) max | 0.035% | 0.030% | 0.030% | 0.030% |
| Phosphorus (P) max | 0.035% | 0.030% | 0.030% | 0.030% |
⚙️ Key Differences Between EN19 and Its Variants
| Grade | Description |
|---|---|
| EN19 | Base grade with standard alloy content. Suitable for general high-tensile use. |
| EN19A | Lower sulphur and phosphorus → better weldability and toughness. |
| EN19B | Tighter chemistry control and slightly higher carbon → improved strength and consistency. |
| EN19C | Higher carbon content → better hardenability and fatigue resistance. Used in critical high-stress parts. |
📌 Typical Applications
| Grade | Common Uses |
|---|---|
| EN19 | Shafts, axles, gears, spindles, forged components |
| EN19A | Welded structures, precision machine parts, automotive linkages |
| EN19B | Transmission shafts, pinions, high-load axles |
| EN19C | High-stress gears, crankshafts, aircraft fittings, heavy-duty machine parts |
🔧 Mechanical Properties (After Heat Treatment)
| Property | EN19 | EN19B | EN19C |
|---|---|---|---|
| Tensile Strength | 850–1000 MPa | 900–1050 MPa | 1000–1150 MPa |
| Yield Strength | ~700 MPa | ~750 MPa | ~800 MPa |
| Case Hardness (surface) | ~55 HRC | 56–58 HRC | 58+ HRC |
| Toughness | Good | Very Good | Excellent (if tempered correctly) |
Note: Properties may vary with heat treatment and section size. All grades can be induction hardened or oil-quenched for deeper strength profiles.
🏭 Steelmet Industries – Stocking All Variants
At Steelmet Industries, we offer all major EN19 variants in a wide range of forms and conditions:
Rounds, Flats, Hexagons, Squares
Supplied in Hot Rolled, Forged, Peeled, Turned, Ground, Drawn or Bright Bar form
VD route (Vacuum Degassed) material available for improved reliability
Supplied with test certificates, traceability, and dimensional assurance
Customers across forging, machining, defense, and automotive sectors depend on us for both prototype batches and scheduled high-volume supplies.
🧠 Frequently Asked Questions
Q1: Are EN19 variants interchangeable?
A: Technically yes for non-critical parts, but EN19B and EN19C are better suited for higher stress or fatigue-prone applications.
Q2: Can EN19 be welded easily?
A: EN19A offers better weldability due to its lower sulphur and phosphorus. Pre-heating and post-weld stress relieving are recommended for all variants.
Q3: What is the international equivalent of EN19?
A: AISI 4140 (USA), 42CrMo4 (Europe), SCM440 (Japan), 708M40 (UK EN system).
Q4: Can I get EN19 bright bars in small quantities?
A: Yes. Steelmet Industries supplies small to large quantities of EN19 and its variants, with customization in length, tolerances, and finish.
🧾 Conclusion
EN19, EN19A, EN19B, and EN19C are not just alphabetical extensions — they’re engineered for different purposes. From general machine parts to high-performance forged components, understanding these variants allows for more efficient design, longer component life, and lower production risks.
Professionals across India and beyond count on reliable sources to provide the right steel — in the right form, at the right time.
For assistance in choosing or sourcing the right EN19 variant, our team is always available.
📲 Connect with us directly on WhatsApp or drop a line through our contact form — let’s make sure you get the steel your product deserves.
