4140 Steel Grade Equivalent – Global Cross Reference You Can Trust
If you’re sourcing 4140 steel grade equivalent across different markets, you’ve probably hit a wall of confusing designations. Is EN19 the same as 4140? Can SCM440 or 42CrMo4 be substituted directly? 🤔
Don’t worry—we get this question all the time from engineers, buyers, and project managers who work with international suppliers.
Let’s walk you through it—clearly, practically, and with real engineering data. 🌍🛠️
📌 What Is AISI 4140?
AISI 4140 is a chromium-molybdenum alloy steel that’s well-known for:
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High strength and wear resistance
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Great hardenability (can be heat treated deeply)
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Solid fatigue performance
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Good machinability in pre-hardened or annealed states
It’s a favorite in sectors like:
🔧 Automotive: axles, crankshafts, steering knuckles
⛽ Oil & Gas: tool joints, drill collars
🚜 Machinery: pins, gears, shafts
🛡️ Defense & Aerospace: bolts, structural brackets, firing components
But if you’re working across borders, you may need to look up the 4140 steel equivalent in Europe, Asia, or other global markets.
🌐 Global Equivalents of 4140 Steel (by Standard)
Here’s a breakdown of 4140 steel equivalent standards used internationally:
| 🌎 Region / Standard | Equivalent Grade | Notes |
|---|---|---|
| USA (SAE/ASTM) | AISI 4140 | Base grade |
| Europe (EN) | EN19 / 42CrMo4 | Most common 4140 steel equivalent in Europe |
| Germany (DIN) | 1.7225 / 42CrMo4 | Precise DIN equivalent of 4140 steel |
| Japan (JIS) | SCM440 | JIS equivalent to 4140 steel |
| China (GB) | 42CrMo | Similar chemistry, often used interchangeably |
| India (IS) | 40Cr4Mo3 / EN19 | Popular 4140 steel equivalent in India |
| UK (BS) | EN19 | Very close in mechanical properties |
| France (AFNOR) | 42CD4 | Acceptable for most general use |
💡 All of these materials fall into the Cr-Mo medium-carbon alloy steel family. They’re designed to balance strength, toughness, and heat treatability.
🔬 Mechanical Properties of 4140 and Its Equivalents
After proper heat treatment (typically quenched and tempered), these steels deliver impressive mechanical strength. Here’s a quick SAE 4140 steel grade comparison with global equivalents:
| Grade | UTS (MPa) | YS (MPa) | Hardness (HRC) | Elongation (%) |
|---|---|---|---|---|
| AISI 4140 | 850–1000 | ~655 | 28–32 | ~25 |
| EN19 / 42CrMo4 | 850–1000 | ~650–700 | 28–32 | ~20–22 |
| SCM440 (JIS) | 800–980 | ~630 | 27–30 | ~22 |
| EN24 | 850–1000 | ~740 | 30–36 | ~16–18 |
📌 So what’s the deal with 4140 steel vs EN24? EN24 has a bit more nickel, which boosts its toughness and makes it more fatigue-resistant—ideal for aircraft-grade gear parts or racing components.
⚙️ Chemical Composition: How Close Are They Really?
Let’s compare chemical elements between 4140 and its top equivalents:
| Element | AISI 4140 | EN19 (EN) | SCM440 (JIS) | 42CrMo4 (DIN) |
|---|---|---|---|---|
| Carbon (C) | 0.38–0.43% | 0.36–0.44% | 0.38–0.43% | 0.38–0.45% |
| Chromium | 0.80–1.10% | 0.90–1.20% | 0.90–1.20% | 0.90–1.20% |
| Molybdenum | 0.15–0.25% | 0.15–0.30% | 0.15–0.30% | 0.15–0.30% |
| Manganese | 0.75–1.00% | 0.50–0.80% | 0.60–0.85% | 0.60–0.90% |
✅ Bottom line? These steels are nearly interchangeable in terms of chemistry and can be used in similar applications—once heat treated to matching conditions.
🛠️ Real-World Case: Switching from 4140 to EN19
A client in South Africa was building wear-resistant mold bases. They initially sourced AISI 4140 but switched to EN19 due to local availability.
We supplied EN19 plates normalized and UT-tested. The machining results were nearly identical. Their post-heat-treat hardness matched 4140 expectations—saving both lead time and cost. 💸
💬 Key Tip: Don’t Just Match Grades—Match Properties
If you’re comparing EN19 vs 4140 steel, remember:
✅ Same grade name ≠ Same heat treatment or performance
Always check:
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Tensile strength after heat treatment
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Case hardening potential
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Machinability (especially for pre-hardened stock)
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Surface treatment compatibility (nitriding, black oxide, etc.)
🧠 Bonus Tip: 4140 vs 4340 vs 1045
| Property | 4140 | 4340 | 1045 (medium carbon) |
|---|---|---|---|
| Strength | High | Higher | Moderate |
| Toughness | High | Very High | Moderate |
| Weldability | Fair | Poor | Good |
| Hardenability | High | Very High | Low |
| Cost | Medium | High | Low |
4140 gives you the sweet spot between cost, strength, and versatility.
🏭 Why Choose Otai Steel for 4140 & Its Global Equivalents?
At Otai, we don’t just stock steel—we solve sourcing problems.
🔧 Whether you’re looking for 4140, EN19, SCM440, or DIN 42CrMo4, we deliver ready-to-machine solutions.
✨ Why Top Brands Trust Us:
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📦 10,000+ tons in stock – 6mm to 300mm thick
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🧪 Full mill certificates + optional 3rd-party inspections (SGS, BV)
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🔥 Heat-treated states: annealed, Q&T, normalized, or nitrided
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📐 Custom cutting, grinding, and finishing to drawing
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🌍 Exporting to 50+ countries – fast global delivery
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🤝 Partners include Thyssenkrupp, Borealis, Schlumberger
📧 jack@otaisteel.com
📱 WhatsApp: +8676923190193
❓FAQs – 4140 Steel Grade Equivalent
Q1: What is the closest European equivalent to AISI 4140?
👉 That would be EN19 / 42CrMo4, which are widely used across Europe.
Q2: Is EN19 interchangeable with AISI 4140?
✅ Yes, especially after matched heat treatment. They’re often cross-certified.
Q3: What is the JIS equivalent to 4140 steel?
🗾 That would be SCM440, used across Japan and Southeast Asia.
Q4: Can EN24 replace 4140?
🛠️ In high-performance parts, yes—but EN24 is tougher and harder, and may be overkill for general use.
Q5: Do you offer Q&T or annealed EN19/SCM440/42CrMo4?
💯 Absolutely! We supply all major 4140 steel grade equivalent types in your required condition.
