4140 equivalent grades: ASTM, EN, JIS, GB, DIN
Cross-reference for 4140 across standard systems. Each match is graded so you can see how safe the substitution is. Chromium-molybdenum low-alloy steel (chromoly) — full 4140 data sheet.
Cross-reference table
| Grade | System | Match | Why / differences |
|---|---|---|---|
| 708M40 (EN19) | BS (superseded British) | Identical | BS 970 708M40: C 0.36–0.44, Cr 0.90–1.20, Mo 0.15–0.25. |
| 42CrMo4 | EN (European) | Identical | 1.7225: C 0.38–0.45, Cr 0.90–1.20, Mo 0.15–0.30 — windows overlap almost completely; dual-certified 4140/42CrMo4 bar is standard. |
| 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. |
| 4142 | AISI / SAE | Near | C 0.40–0.45 — the upper half of the 42CrMo4 range; slightly higher hardness. |
| 4130 | AISI / SAE | Near | 0.30 % C version: lower strength (≈ 1000 MPa max practical), far better weldability; used for tube and welded structures. |
| 40KhM / 38KhM | GOST (Russia/CIS) | Near | GOST 4543 38KhM (C 0.35–0.42) / 40KhMFA (V-bearing); 40KhM is the common Russian equivalent in practice. |
| 4340 | AISI / SAE | Functional | Adds 1.8 % Ni: deeper hardenability (sections > 100 mm), higher toughness at 1500+ MPa. |
| 1045 | AISI / SAE | Functional | Unalloyed medium-carbon: cheaper, through-hardens only ≤ 20 mm. |
Identical = same composition and mechanical limits within rounding. Near = one limit differs (e.g. carbon max or impact temperature). Functional = interchangeable for most uses after an engineering check.
How the matches are graded
Identical means the chemical composition windows overlap so that material certified to one specification meets the other without deviation, and the mechanical minimums are the same or the other is inside them — mills usually dual-certify. Near means one limit differs (a carbon maximum, an impact temperature, a strength minimum or a delivery condition) and a substitution needs a one-line engineering check. Functional means the grades serve the same purpose but are not the same steel — a designer can often use one for the other, but only after re-checking the design.
4140 in BS (superseded British)
- 708M40 (EN19) — Identical BS 970 708M40: C 0.36–0.44, Cr 0.90–1.20, Mo 0.15–0.25.
4140 in EN (European)
- 42CrMo4 — Identical 1.7225: C 0.38–0.45, Cr 0.90–1.20, Mo 0.15–0.30 — windows overlap almost completely; dual-certified 4140/42CrMo4 bar is standard.
4140 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.
4140 in JIS (Japan)
- SCM440 — Identical JIS G4053 SCM440: C 0.38–0.43, Cr 0.90–1.20, Mo 0.15–0.30.
4140 in AISI / SAE
- 4142 — Near C 0.40–0.45 — the upper half of the 42CrMo4 range; slightly higher hardness.
- 4130 — Near 0.30 % C version: lower strength (≈ 1000 MPa max practical), far better weldability; used for tube and welded structures.
- 4340 — Functional Adds 1.8 % Ni: deeper hardenability (sections > 100 mm), higher toughness at 1500+ MPa.
- 1045 — Functional Unalloyed medium-carbon: cheaper, through-hardens only ≤ 20 mm.
4140 in GOST (Russia/CIS)
- 40KhM / 38KhM — Near GOST 4543 38KhM (C 0.35–0.42) / 40KhMFA (V-bearing); 40KhM is the common Russian equivalent in practice.
Superseded names for 4140
- G41400 — UNS: 4140H = H41400 (hardenability band).
- 42CrMo4 / 1.7225 — EN 10083-3: European twin; 42CrMoS4 (1.7227) free-machining.
- 708M40 / 708A42 / EN19 — BS 970 (withdrawn): EN19 is the old British name still used in the UK and India.
- SCM440 — JIS G4053: Japanese twin (SCM4 in older editions).
- 4145H / 4145H Mod — API Spec 7-1: Higher-carbon variant for drill collars and tool joints.
Key data for 4140
Full composition, mechanical properties by thickness, heat treatment and applications for 4140 →
Verified against ASTM A29/A29M-20 (SAE J404 chemistry). Last checked: September 2026.