42CrMo4 equivalent grades: ASTM, EN, JIS, GB, DIN
42CrMo4 is chromium-molybdenum steel for quenching and tempering specified in EN 10083-3. Every grade in the database that can stand in for it is listed below, drawn from 6 standard systems, each with the reason it does or does not match exactly. The full 42CrMo4 data sheet carries the composition and mechanical tables.
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42CrMo4 is cross-certified with 4140, 708M40, 42CrMo and 1 more: the composition windows overlap closely enough that one certificate satisfies the other. 4140, 42CrMoS4, 40KhM / 38KhM differ on one limit only — a carbon ceiling, an impact temperature or a strength minimum. 080M40, 34CrNiMo6, C45 serve in the same applications, but the composition differs enough that the engineer signs it off, not the buyer. The table holds 2 in AISI / SAE, 2 in BS (superseded British), 1 in GB/T (China), 1 in JIS (Japan), 3 in EN (European), 1 in GOST (Russia/CIS).
Cross-reference table
| Grade | System | Match | Why / differences |
|---|---|---|---|
| 4140 | AISI / SAE | Identical | AISI 4140 (UNS G41400): C 0.38–0.43, Cr 0.80–1.10, Mo 0.15–0.25, Mn 0.75–1.00. Windows overlap almost completely; mills dual-certify 42CrMo4/4140. |
| 708M40 | BS (superseded British) | Identical | BS 970 708M40: C 0.36–0.44, Cr 0.90–1.20, Mo 0.15–0.25. |
| 42CrMo | GB/T (China) | Identical | GB/T 3077 42CrMo: C 0.38–0.45, Cr 0.90–1.20, Mo 0.15–0.25. |
| SCM440 | JIS (Japan) | Identical | JIS G4053 SCM440: C 0.38–0.43, Cr 0.90–1.20, Mo 0.15–0.30 — matches 42CrMo4 exactly on Cr and Mo. |
| 4140 | AISI / SAE | Near | C 0.40–0.45 — covers the upper half of the 42CrMo4 carbon range. |
| 42CrMoS4 | EN (European) | Near | Same grade with controlled S (0.020–0.040 %) for free machining; slightly lower transverse toughness. |
| 40KhM / 38KhM | GOST (Russia/CIS) | Near | GOST 4543 38KhM (C 0.35–0.42, Cr 0.90–1.30, Mo 0.20–0.30); 40KhM is the nearer Russian practice grade. |
| 080M40 | BS (superseded British) | Functional | The alloy step up, equivalent to 709M40 (EN19). Substitute where hardenability in sections above about 60 mm or genuine toughness is required — 080M40 cannot deliver either. |
| 34CrNiMo6 | EN (European) | Functional | Ni-bearing alternative with deeper hardenability for sections above ~100 mm. |
| C45 | EN (European) | Functional | Unalloyed, cheaper, but through-hardens only in thin sections. |
Identical, near and functional are defined once on the grade index; the reason column below says which limit differs in each case.
42CrMo4 in AISI / SAE
- 4140 — Identical AISI 4140 (UNS G41400): C 0.38–0.43, Cr 0.80–1.10, Mo 0.15–0.25, Mn 0.75–1.00. Windows overlap almost completely; mills dual-certify 42CrMo4/4140.
- 4140 — Near C 0.40–0.45 — covers the upper half of the 42CrMo4 carbon range.
42CrMo4 in BS (superseded British)
- 708M40 — Identical BS 970 708M40: C 0.36–0.44, Cr 0.90–1.20, Mo 0.15–0.25.
- 080M40 — Functional The alloy step up, equivalent to 709M40 (EN19). Substitute where hardenability in sections above about 60 mm or genuine toughness is required — 080M40 cannot deliver either.
42CrMo4 in GB/T (China)
- 42CrMo — Identical GB/T 3077 42CrMo: C 0.38–0.45, Cr 0.90–1.20, Mo 0.15–0.25.
42CrMo4 in JIS (Japan)
- SCM440 — Identical JIS G4053 SCM440: C 0.38–0.43, Cr 0.90–1.20, Mo 0.15–0.30 — matches 42CrMo4 exactly on Cr and Mo.
42CrMo4 in EN (European)
- 42CrMoS4 — Near Same grade with controlled S (0.020–0.040 %) for free machining; slightly lower transverse toughness.
- 34CrNiMo6 — Functional Ni-bearing alternative with deeper hardenability for sections above ~100 mm.
- C45 — Functional Unalloyed, cheaper, but through-hardens only in thin sections.
42CrMo4 in GOST (Russia/CIS)
- 40KhM / 38KhM — Near GOST 4543 38KhM (C 0.35–0.42, Cr 0.90–1.30, Mo 0.20–0.30); 40KhM is the nearer Russian practice grade.
Superseded names for 42CrMo4
- 42CrMo4 (1.7225) — DIN 17200 (withdrawn): Name and number unchanged since DIN 17200; only the standard moved to EN 10083-3.
- 708M40 / 708A42 — BS 970
- 42CD4 — NF A 35-552
- 42CrMo4 — UNI 7845
Key data for 42CrMo4
Full composition, mechanical properties by thickness, heat treatment and applications for 42CrMo4 →
Verified against EN 10083-3:2006. Last checked: September 2026.