40CrMnMo7 vs M42: 33% composition overlap. Significantly different materials serving different application areas.
40CrMnMo7 vs M42
Side-by-side chemical composition and mechanical property comparison.
Overview
40CrMnMo7
1.2311
Pre-hardened plastic mold steel — delivered at 28-32 HRC, ready for machining without further heat treatment. The European equivalent of AISI P20. Cr-Mn-Mo composition for good through-hardenability in large sections. THE workhorse mold base material for injection molds, compression molds, and die casting dies. Good machinability, polishability, and photo-etchability. Used for mold frames, large injection molds, blow molds, and structural die components.
M42
1.3247
Cobalt super high speed steel — 8% Co for maximum hot hardness (HRC 69 at 550°C). THE HSS for machining superalloys, titanium, and pre-hardened steels where M2 burns out. Mo-series (not W-series like T15). Reaches HRC 68-70 after hardening — among the hardest HSS grades. Also known as HS2-9-1-8 (EN) or SKH59 (JIS). Used for drills, end mills, taps, broaches, and milling cutters for difficult-to-machine materials.
| 40CrMnMo7 | M42 | |
|---|---|---|
| Material Number | 1.2311 | 1.3247 |
| Category | Tool Steel | Tool Steel |
| Standard | EN ISO 4957 | EN ISO 4957 |
Chemical composition (wt%)
| Element | 40CrMnMo7 | M42 | Overlap |
|---|---|---|---|
| C | 0.35–0.45% | 1.05–1.15% | No overlap |
| Si | 0.2–0.4% | 0–0.65% | OK |
| Mn | 1.3–1.6% | 0–0.4% | No overlap |
| P | 0–0.03% | 0–0.03% | OK |
Mechanical properties
| Property | 40CrMnMo7 | M42 | Unit |
|---|---|---|---|
| tensile_strength | 900–1050 | — | MPa |
| yield_strength | 700–800 | — | MPa |
| hardness_hrc | 28–32 | 68–70 | HRC |
Compatibility Assessment
40CrMnMo7 and M42 have significantly different compositions (33% overlap). These materials are not interchangeable and serve different application areas.
Automated assessment based on composition analysis
Frequently Asked Questions
Is 40CrMnMo7 the same as M42?
40CrMnMo7 and M42 have a 33% composition overlap. They are generally not directly interchangeable.
Can I replace 40CrMnMo7 with M42?
Generally not recommended. The compositions differ significantly (33% overlap). These materials have different alloying concepts and are intended for different applications.
What is the difference between 40CrMnMo7 and M42?
The main differences are in the following elements: C, Mn, Cr, Mo. 40CrMnMo7 is a Tool Steel grade, while M42 is a Tool 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.