4140 / 42CrMo4 Quenched & Tempered Steel
4140 / 42CrMo4 Quenched & Tempered Steel is supplied for mechanical engineering and serial production applications where the grade, delivery condition, dimensional tolerance and traceability must be specified together. Erkal Haddecilik supplies cut-to-length steel from Bursa subject to stock.
Key properties
- +QT means quenched-and-tempered delivery condition, not a separate steel grade.
- Compare SAE 4140 and EN 42CrMo4 after checking chemistry, product standard and delivery condition.
Typical applications
- Machine shafts and axles with specified strength and delivery condition.
- Transmission components selected against loading, section and heat-treatment requirements.
42CrMo4 — producer EN reference composition
| Element | Range |
|---|---|
| C | 0,38–0,45 % |
| Si | 0,10–0,40 % |
| Mn | 0,60–0,90 % |
| Cr | 0,90–1,20 % |
| Mo | 0,15–0,30 % |
| P | ≤0,025 % |
| S | ≤0,035 % |
This table summarizes the EN reference row for 42CrMo4 in the Ovako datasheet. It is not an acceptance table for other standard names mentioned on this page. Specify the complete standard and check the delivery certificate.
Values may vary by product standard or variant; the material certificate is the basis for purchasing specifications.
Heat treatment guide
| Process | Temperature | Note |
|---|---|---|
| Soft annealing | 680–720 °C | Slow cooling |
| Quench and temper – austenitizing | 840–880 °C | Quenching in oil or water |
| Tempering | 540–680 °C | According to target mechanical properties |
| Stress relieving | 450–650 °C | Air cooling |
Stress-relieving temperature depends on delivery condition. For +QT material it must remain below the previous tempering temperature; verify a process that preserves the specified strength and hardness. The table range is not a recipe for every delivery. Lucefin 42CrMo4 (rev. 2018)
Heat treatment values are indicative; the process specification must be established separately for the part section, furnace, cooling medium and target mechanical properties.
Technical selection note
Steel grades must not be considered exact equivalents based on similar names alone. Chemical composition, mechanical properties, product standard, delivery condition and heat treatment requirements must be verified against the certificate.
Frequently Asked Questions
Technical selection note
Material equivalence, mechanical properties and heat treatment must be verified against the applicable standard and material certificate before critical use.