30CrNiMo8 vs 40CrNiMo6: 40% composition overlap. Significantly different materials serving different application areas.
30CrNiMo8 vs 40CrNiMo6
Side-by-side chemical composition and mechanical property comparison.
Overview
30CrNiMo8
1.6580
High-strength quenched and tempered Cr-Ni-Mo steel for very large cross-sections. Even better hardenability than 34CrNiMo6 due to higher Cr and Ni content. Used for large shafts (>200mm diameter), heavy-duty gears, turbine rotors, and critical aerospace components.
40CrNiMo6
1.6565
High-strength Cr-Ni-Mo quench and temper steel. Higher C than 34CrNiMo6 for greater strength, with excellent hardenability from Ni+Mo combination. Used for heavy-duty crankshafts, connecting rods, high-strength bolts (class 12.9), gears, and critical structural components in large cross-sections.
| 30CrNiMo8 | 40CrNiMo6 | |
|---|---|---|
| Material Number | 1.6580 | 1.6565 |
| Category | Alloy Steel | Alloy Steel |
| Standard | EN 10083-3 | EN 10083-3 |
Chemical composition (wt%) — Pro
| Element | 30CrNiMo8 | 40CrNiMo6 | Overlap |
|---|---|---|---|
| C | 0.26–0.34% | 0.36–0.44% | No overlap |
| Si | 0–0.4% | 0–0.4% | OK |
| Mn | 0.3–0.6% | 0.5–0.8% | Partial |
| P | 0–0.025% | 0–0.025% | OK |
| S | |||
| Cr | |||
| Mo | |||
| Ni |
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Sign up free — 3 comparisons/day freeMechanical properties — Pro
| Property | 30CrNiMo8 | 40CrNiMo6 | Unit |
|---|---|---|---|
| Tensile Strength | 1000–1200 | 1000–1200 | MPa |
| Yield Strength | ≥ 800 | ≥ 800 | MPa |
| Elongation | ≥ 11 | ≥ 10 | % |
| Hardness HRC | |||
| Elastic Modulus | |||
| Density |
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Sign up free — 3 comparisons/day freeCompatibility Assessment
30CrNiMo8 and 40CrNiMo6 have significantly different compositions (40% overlap). These materials are not interchangeable and serve different application areas.
Automated assessment based on composition analysis
Frequently Asked Questions
Is 30CrNiMo8 the same as 40CrNiMo6?
30CrNiMo8 and 40CrNiMo6 have a 40% composition overlap. They are generally not directly interchangeable.
Can I replace 30CrNiMo8 with 40CrNiMo6?
Generally not recommended. The compositions differ significantly (40% overlap). These materials have different alloying concepts and are intended for different applications.
What is the difference between 30CrNiMo8 and 40CrNiMo6?
The main differences are in the following elements: C, Mn, Cr, Mo. 30CrNiMo8 is a Alloy Steel grade, while 40CrNiMo6 is a Alloy Steel grade.
Related Comparisons
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Data provided for reference only. Always verify against the applicable specification for critical applications.
All data is for reference only. Equivalents indicate similarity, not identity. Always verify against the applicable specification for safety-critical applications. materialref.com accepts no liability for decisions based on this data.