Low carbon case hardening steels like EN32, EN32A, EN32B, and 080M15 are vital in applications where a tough, machinable core is needed, but the surface requires hardening. This detailed comparison explains how each grade under BS 970 differs and helps buyers choose the most suitable material for gears, pins, bushes, camshafts, and automotive parts.
At Steelmet Industries, we offer customized bright and black bars in all these grades with complete traceability and tailored solutions for forging and machining needs.
📊 Comparative Table
| Grade | Standard | Carbon % | Manganese % | Case Depth | Hardness after Carburizing (HRC) | Common Use |
|---|---|---|---|---|---|---|
| EN32 | BS 970:1955 | 0.10–0.15 | 0.40–0.70 | 0.75–1.25 mm | 55–62 HRC | Gears, cams, mild-duty shafts |
| EN32A | BS 970:1955 | 0.10–0.15 | 0.50–0.90 | 0.75–1.25 mm | 58–62 HRC | Pins, bushes, timing sprockets |
| EN32B | BS 970:1955 | 0.12–0.18 | 0.90–1.20 | 0.75–1.25 mm | 58–63 HRC | High-load pins, transmission parts |
| EN32C | BS 970:1955 | 0.13–0.18 | 0.70–1.00 | 0.75–1.25 mm | 58–63 HRC | Heavy-duty linkages, bearings |
| 080M15 | BS 970:1991 | 0.13–0.18 | 0.60–0.90 | 0.75–1.25 mm | 58–62 HRC | Automotive cams, bushes, rollers |
| 070M20 | BS 970:1991 | 0.15–0.25 | 0.50–0.80 | 1.0–1.5 mm | 58–63 HRC | Mild shafts, wear-resistant parts |
🔍 Key Differences Explained
✅ EN32 vs EN32A
EN32A has slightly higher manganese content, offering better hardenability and improved machinability. It’s more commonly used in modern setups than legacy EN32.
✅ EN32A vs EN32B
EN32B provides better wear resistance due to higher manganese levels. Ideal where repetitive surface impact is expected.
✅ EN32 Family vs 080M15
080M15 is the modern equivalent of EN32A, as per BS 970:1991. Chemically and mechanically, both are very similar. If you’re ordering new production, 080M15 is generally preferred.
✅ EN32 Family vs 070M20
Though not strictly a case-hardening grade, 070M20 is often carburized for similar applications but has slightly higher carbon content. It bridges the gap between low carbon and medium carbon steels.
🏭 Applications Across Industries
Automotive: Gears, sprockets, clutch hubs
Textile Machinery: Bushes, pins, low-wear moving parts
Agricultural Equipment: Linkages, couplings, housings
Forgings: Case-hardened forged blanks with fine grain structure
Steelmet Industries supplies these steels as:
Black Bars (Rolled / Peeled)
Bright Bars (Cold Drawn / Ground)
Custom sizes and shapes
Heat-treated or normalized if needed
✅ Material Selection Tips
For economical case hardening with good machinability → 080M15 / EN32A
For slightly better wear and stress resistance → EN32B
For legacy drawings or old equipment → EN32 / EN32C
For general-purpose mild case hardening → 070M20
🔩 Why choose Steelmet Industries?
With decades of expertise in case hardening steels, Steelmet Industries helps customers not just match a grade — but optimize it. Our detailed heat charts, dimensional consistency, and traceable supply chain ensure every bar meets your exact requirement.
Explore our range, or send your inquiry through our Contact Page or on WhatsApp at +91 712 2728071. Your application deserves the right core and a wear-resistant skin — and we’ll help you get there.
✅ FAQs
Q1. Is 080M15 the same as EN32A?
Yes. 080M15 is the updated designation for EN32A as per BS 970:1991.
Q2. Can EN32 steels be welded?
They can be welded but pre-heating and post-weld stress relief is recommended due to low carbon content and case-hardened layer.
Q3. Are these steels suitable for induction hardening?
Not recommended. They’re ideal for carburizing or gas nitriding rather than flame or induction hardening.
Q4. Can Steelmet supply normalized EN32 steel?
Yes. We supply in rolled, normalized, or annealed condition as per customer request.
