EN24 Steel Hardening Job Work
Precision EN24 (817M40 / SAE 4340) steel hardening job work — nickel-chromium-molybdenum alloy for high-stress shafts, spindles, heavy engineering & aerospace-grade components. 55–62 HRC with certified Rockwell reports.
Maximum Strength. Surface & Core.
Looking for reliable EN24 steel hardening job work? EN24 (817M40) is a nickel-chromium-molybdenum alloy steel — the premium grade chosen when fatigue life, impact resistance and surface hardness must coexist under the most demanding conditions. Equivalent to SAE 4340, it's specified for aerospace components, heavy-duty gearbox shafts, high-speed spindles and defence-grade applications. Thakur Industries provides precision induction hardening for EN24 steel from our Ludhiana facility, achieving 55–62 HRC with fully certified Rockwell hardness reports.
EN24 Applications
EN24's nickel content boosts impact toughness; chromium and molybdenum provide high hardenability and temper resistance. The result is a steel that can be hardened to 55–62 HRC at the surface while the core absorbs shock loads without cracking — critical for aircraft landing-gear pins, high-speed machine spindles, press-tool components and heavy gear shafts.
Why EN24 for Critical Applications?
- Highest hardenability of the EN-series — uniform HRC on large sections
- Nickel adds toughness at hardened state — resists brittle fracture
- SAE 4340 equivalent — accepted for export and OEM specifications
- Superior fatigue life under reversed bending and torsion
- Retains mechanical properties after repeated thermal cycling
// SPECIFICATIONS //
EN24 Hardening Specifications
| Material Grade | EN24 · 817M40 · SAE 4340 · 36CrNiMo4 |
|---|---|
| Alloy System | Nickel-Chromium-Molybdenum (Ni-Cr-Mo) |
| Surface Hardness | 55–62 HRC (certified Rockwell report) |
| Core Hardness | 35–45 HRC (hardened & tempered) |
| Case Depth | 0.5 mm – 3 mm (controlled to spec) |
| Component Size | Diameter 15–250 mm, length up to 2000 mm |
| Heating Temperature | 850–900 °C (induction) |
| Quench Medium | Polymer / oil-based, controlled |
| Turnaround | 2–4 working days (standard) |
| Testing | HRC verification, case-depth check, dimensional inspection |
// HRC RANGE //
EN24 Induction Hardening HRC Range
The EN24 induction hardening HRC range is the highest in the EN-series. EN24 (817M40 / 4340) reaches 55–62 HRC at the surface while its nickel-chromium-molybdenum core stays tough — the table below summarises the hardness, case depth, alloy content and austenitizing temperature you can specify.
| Property | Value |
|---|---|
| Surface Hardness | 55–62 HRC |
| Core Hardness | 35–45 HRC (hardened & tempered) |
| Case Depth | 0.5–3 mm (controlled to spec) |
| Alloy Content | Ni-Cr-Mo · ~0.36–0.44% C |
| Austenitizing Temp | 850–900 °C |
// PRICING & TURNAROUND //
EN24 Hardening Rates & Lead Time
We offer competitive EN24 steel hardening rates for both prototype batches and bulk OEM production. Final pricing depends on component weight, diameter, case depth and quantity — share your drawing for an exact quote within 24 hours.
Pricing Basis
Per kg or per piece, with reduced rates on bulk and repeat OEM orders.
Minimum Order
No rigid minimum — single trial EN24 parts to multi-thousand-piece lots accepted.
Turnaround
Standard 2–4 working days; urgent same-week jobs for regular clients.
// WHY CHOOSE US //
Why OEMs Trust Thakur Industries
Consistent 55–62 HRC
Repeatable certified hardness on every EN24 part, batch after batch.
Certified Reports
Rockwell hardness and case-depth documentation for OEM supply chains.
Years of Experience
Trusted by Ludhiana’s automotive, tractor and heavy-engineering makers.
Fast Turnaround
2–4 day standard delivery keeps your production line running.
// MATERIAL GRADES //
Related Material Grades
EN24 sits at the top of the EN-series. Compare it with the other gear and shaft steels we induction-harden — explore our dedicated material-grade pages for hardness, case depth and application detail:
EN24 Steel Hardening FAQs
Learn more about the metallurgy of alloy-steel surface hardening from the ASM International heat-treatment resources.
Last updated: June 2026 · Thakur Industries, Ludhiana, Punjab
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