EN24 Alloy Steel
Comparable Standards
| Designation | Standard |
| BS 970:1962 | EN24 |
| AISI/SAE | 4340 |
| UNS | G43400 |
Chemical Composition (wt %)
| C | Si | Mn | P (max) | S (max) | Cr | Ni | Mo |
| 0.38–0.43 | 0.10–0.40 | 0.60–0.90 | 0.035 | 0.035 | 1.30–1.65 | 1.30–1.65 | 0.25–0.35 |
Mechanical Properties
| Property | Value |
| Typical Hardness | 46–54 HRC |
| Tensile Strength | 850 MPa |
Heat Treatment Guidelines
– Annealing: 680–700 °C; slow cool
– Tempering: 540–620 °C; as required
Typical Applications
– Gears
– Shafts
– Spindles
– Aerospace components
Supply Formats & Services
– Stocked Shapes: Rounds (20 – 350 mm Ø), Flats (25 × 50 – 200 × 500 mm), Blocks (up to 2,000 kg)
– Custom Cutting: Precision bandsaw to drawing
– Value-Added Services: In-house forging & heat treatment, Ultrasonic (UT) & MPI testing, Hardness & microstructure analysis, Pre-machining & surface grinding
Certifications & Quality Assurance
– Mill-Traceable Test Certificates (EN 10204 3.1)
– Ultrasonic & MPI Reports (ASTM A388 on request)
– Hardness, Grain-Size & Decarb Analysis
– ISO 9001:2015 (certification in process)
Logistics & Enquiry
– Same-day Dispatch for stocked items from Kolkata
– 24–48 hr turnaround on custom-cut materials
– PAN-India Delivery via trusted logistics partners