1045 equivalent grades: ASTM, EN, JIS, GB, DIN
Cross-reference for 1045 across standard systems. Each match is graded so you can see how safe the substitution is. Medium-carbon steel, hardenable — full 1045 data sheet.
Cross-reference table
| Grade | System | Match | Why / differences |
|---|---|---|---|
| 080M46 | BS (superseded British) | Identical | BS 970 080M46: C 0.42–0.50, Mn 0.60–1.00. |
| C45 | EN (European) | Identical | 1.0503: C 0.42–0.50, Mn 0.50–0.80; C45E (1.1191) the cleaner version — dual-certified 1045/C45 bar is standard. |
| 45 | GOST (Russia/CIS) | Identical | GOST 1050 Steel 45: C 0.42–0.50, Mn 0.50–0.80. |
| S45C | JIS (Japan) | Identical | JIS G4051 S45C: C 0.42–0.48, Mn 0.60–0.90. |
| 1050 | AISI / SAE | Near | C 0.48–0.55: slightly higher carbon and hardness for the same treatments. |
| 1040 | AISI / SAE | Near | C 0.37–0.44: slightly lower carbon, better weldability. |
| 4140 | AISI / SAE | Functional | Alloyed alternative with deep hardenability for sections > 25 mm and higher toughness. |
| 1144 | AISI / SAE | Functional | Resulfurized 0.44 % C free-machining bar ('Stressproof') for high-volume screw-machine shafts. |
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.
1045 in BS (superseded British)
- 080M46 — Identical BS 970 080M46: C 0.42–0.50, Mn 0.60–1.00.
1045 in EN (European)
- C45 — Identical 1.0503: C 0.42–0.50, Mn 0.50–0.80; C45E (1.1191) the cleaner version — dual-certified 1045/C45 bar is standard.
1045 in GOST (Russia/CIS)
- 45 — Identical GOST 1050 Steel 45: C 0.42–0.50, Mn 0.50–0.80.
1045 in JIS (Japan)
- S45C — Identical JIS G4051 S45C: C 0.42–0.48, Mn 0.60–0.90.
1045 in AISI / SAE
- 1050 — Near C 0.48–0.55: slightly higher carbon and hardness for the same treatments.
- 1040 — Near C 0.37–0.44: slightly lower carbon, better weldability.
- 4140 — Functional Alloyed alternative with deep hardenability for sections > 25 mm and higher toughness.
- 1144 — Functional Resulfurized 0.44 % C free-machining bar ('Stressproof') for high-volume screw-machine shafts.
Superseded names for 1045
- C1045 — AISI (pre-1960s)
- G10450 — UNS: 1045H = H10450 hardenability band.
- 080M46 / 080A47 — BS 970: 080M46 ≈ 1045 (Mn 0.60–1.00).
- C45 / Ck45 / C45E — EN 10083 / DIN 17200: European twins.
- XC45 / XC48 — NF A 35-552
Key data for 1045
Full composition, mechanical properties by thickness, heat treatment and applications for 1045 →
Verified against ASTM A29/A29M-20 (SAE J403 chemistry). Last checked: September 2026.