18CrNiMo7-6 vs 30CrMo4: 57% composition overlap. Moderate differences, generally not direct substitutes.
18CrNiMo7-6 vs 30CrMo4
Side-by-side chemical composition and mechanical property comparison.
Overview
18CrNiMo7-6
1.6587
Premium Cr-Ni-Mo case-hardening steel for the most demanding gear applications. Excellent core toughness and hardenability for large cross-sections. The standard gear steel for wind turbines, heavy-duty gearboxes, and aerospace gearing.
30CrMo4
1.7218
Low-to-medium carbon Cr-Mo QT steel — lower C than 34CrMo4/42CrMo4 giving better weldability and toughness. THE gas cylinder and pressure vessel grade in Europe (EN ISO 9809). Good hardenability for medium sections. Also used for automotive crankshafts, gears, and high-pressure hydraulic components. AISI 4130 equivalent.
| 18CrNiMo7-6 | 30CrMo4 | |
|---|---|---|
| Material Number | 1.6587 | 1.7218 |
| Category | Alloy Steel | Alloy Steel |
| Standard | EN 10084 | EN 10083-3 |
Chemical composition (wt%)
| Element | 18CrNiMo7-6 | 30CrMo4 | Overlap |
|---|---|---|---|
| C | 0.15–0.21% | 0.26–0.33% | No overlap |
| Si | 0–0.4% | 0–0.4% | OK |
| Mn | 0.5–0.9% | 0.6–0.9% | OK |
| P | 0–0.025% | 0–0.025% | OK |
Mechanical properties
| Property | 18CrNiMo7-6 | 30CrMo4 | Unit |
|---|---|---|---|
| hardness_hrc | 58–62 | — | HRC |
| tensile_strength | 1050–1350 | 800–950 | MPa |
| hardness_hb | ≤ 229 | 230–280 | HB |
Compatibility Assessment
18CrNiMo7-6 and 30CrMo4 have moderate differences (57% overlap). They are generally not direct substitutes. Consider the specific requirements of your application.
Automated assessment based on composition analysis
Frequently Asked Questions
Is 18CrNiMo7-6 the same as 30CrMo4?
18CrNiMo7-6 and 30CrMo4 have a 57% composition overlap. They are generally not directly interchangeable.
Can I replace 18CrNiMo7-6 with 30CrMo4?
Generally not recommended. The compositions differ significantly (57% overlap). These materials have different alloying concepts and are intended for different applications.
What is the difference between 18CrNiMo7-6 and 30CrMo4?
The main differences are in the following elements: C, Cr, Mo. 18CrNiMo7-6 is a Alloy Steel grade, while 30CrMo4 is a Alloy Steel grade.
View full data for each material:
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.