C45 equivalent grades: ASTM, EN, JIS, GB, DIN
Cross-reference for C45 across standard systems. Each match is graded so you can see how safe the substitution is. Medium-carbon steel for quenching and tempering — full C45 data sheet.
Cross-reference table
| Grade | System | Match | Why / differences |
|---|---|---|---|
| 1045 | AISI / SAE | Identical | AISI/SAE 1045 (UNS G10450): C 0.43–0.50, Mn 0.60–0.90 — same carbon window; C45 additionally caps Cr/Mo/Ni. Interchangeable in practice. |
| 45 | GOST (Russia/CIS) | Identical | GOST 1050 Steel 45: C 0.42–0.50, Mn 0.50–0.80, Si 0.17–0.37. |
| S45C | JIS (Japan) | Identical | JIS G4051 S45C: C 0.42–0.48, Mn 0.60–0.90; matches C45 within rounding. |
| 080M46 | BS (superseded British) | Near | BS 970 080M46: C 0.42–0.50, Mn 0.60–1.00 — slightly wider Mn. |
| C45E | EN (European) | Near | Same grade with P ≤ 0.030 and guaranteed impact; order C45E when toughness or fine grain matters. |
| 42CrMo4 | EN (European) | Functional | Alloyed alternative with far higher hardenability for the same part geometry above 25 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.
C45 in AISI / SAE
- 1045 — Identical AISI/SAE 1045 (UNS G10450): C 0.43–0.50, Mn 0.60–0.90 — same carbon window; C45 additionally caps Cr/Mo/Ni. Interchangeable in practice.
C45 in GOST (Russia/CIS)
- 45 — Identical GOST 1050 Steel 45: C 0.42–0.50, Mn 0.50–0.80, Si 0.17–0.37.
C45 in JIS (Japan)
- S45C — Identical JIS G4051 S45C: C 0.42–0.48, Mn 0.60–0.90; matches C45 within rounding.
C45 in BS (superseded British)
- 080M46 — Near BS 970 080M46: C 0.42–0.50, Mn 0.60–1.00 — slightly wider Mn.
C45 in EN (European)
- C45E — Near Same grade with P ≤ 0.030 and guaranteed impact; order C45E when toughness or fine grain matters.
- 42CrMo4 — Functional Alloyed alternative with far higher hardenability for the same part geometry above 25 mm.
Superseded names for C45
- Ck45 — DIN 17200 (withdrawn 1987): Ck45 = today's C45E (1.1191). Still the most-used name in German-speaking workshops.
- C45 (1.0503) — DIN 17200: Base quality, number unchanged.
- 080M46 — BS 970 (withdrawn)
- XC45 / XC48 — NF A 35-552
- C45 / C46 — UNI 7845
Key data for C45
Full composition, mechanical properties by thickness, heat treatment and applications for C45 →
Verified against EN 10083-2:2006. Last checked: September 2026.