321 equivalent grades: ASTM, EN, JIS, GB, DIN
321 is austenitic Cr-Ni stainless steel, titanium-stabilized specified in ASTM A240. Below, the grades that can replace it — 6 standard systems in all — with the deciding limit named for each one rather than left to be looked up. The full 321 data sheet carries the composition and mechanical tables.
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321 is cross-certified with 321S31, 1.4541, 06Cr18Ni11Ti and 2 more: the composition windows overlap closely enough that one certificate satisfies the other. 347, 304H, 1.4878 differ on one limit only — a carbon ceiling, an impact temperature or a strength minimum. 304L, 310 serve the same purpose without being the same steel, so a substitution there needs the design re-checked rather than the certificate. Across systems that is 1 in BS (superseded British), 2 in EN (European), 1 in GB/T (China), 1 in GOST (Russia/CIS), 1 in JIS (Japan), 4 in AISI / SAE.
Cross-reference table
| Grade | System | Match | Why / differences |
|---|---|---|---|
| 321S31 | BS (superseded British) | Identical | BS 1449 321S31. |
| 1.4541 | EN (European) | Identical | X6CrNiTi18-10: same limits; dual-certified 321/1.4541. |
| 06Cr18Ni11Ti | GB/T (China) | Identical | GB/T 20878 06Cr18Ni11Ti (formerly 0Cr18Ni10Ti). |
| 08Kh18N10T / 12Kh18N10T | GOST (Russia/CIS) | Identical | GOST 5632 08Kh18N10T (C ≤ 0.08) — the standard Russian austenitic; 12Kh18N10T (C ≤ 0.12) ≈ 321H. |
| SUS321 | JIS (Japan) | Identical | JIS G4304 SUS321: C ≤ 0.08, Cr 17–19, Ni 9–13, Ti ≥ 5×C. |
| 347 | AISI / SAE | Near | S34700 / 1.4550: Nb-stabilized twin; Nb transfers through the arc so weld metal is also stabilized; slightly better creep. Interchangeable in most specs. |
| 304H | AISI / SAE | Near | Unstabilized high-carbon 304 for creep service; sensitizes but is cheaper — used where intergranular corrosion is not a concern. |
| 1.4878 | EN (European) | Near | X8CrNiTi18-10 heat-resisting variant (EN 10095) for furnace parts. |
| 304L | AISI / SAE | Functional | Low-carbon route to weld stability; not suitable above ~425 °C for strength. |
| 310 | AISI / SAE | Functional | Stabilized 18-8 for service to ~870 °C; 310 takes over above that. |
Identical, near and functional are defined once on the grade index; the reason column below says which limit differs in each case.
321 in BS (superseded British)
- 321S31 — Identical BS 1449 321S31.
321 in EN (European)
- 1.4541 — Identical X6CrNiTi18-10: same limits; dual-certified 321/1.4541.
- 1.4878 — Near X8CrNiTi18-10 heat-resisting variant (EN 10095) for furnace parts.
321 in GB/T (China)
- 06Cr18Ni11Ti — Identical GB/T 20878 06Cr18Ni11Ti (formerly 0Cr18Ni10Ti).
321 in GOST (Russia/CIS)
- 08Kh18N10T / 12Kh18N10T — Identical GOST 5632 08Kh18N10T (C ≤ 0.08) — the standard Russian austenitic; 12Kh18N10T (C ≤ 0.12) ≈ 321H.
321 in JIS (Japan)
- SUS321 — Identical JIS G4304 SUS321: C ≤ 0.08, Cr 17–19, Ni 9–13, Ti ≥ 5×C.
321 in AISI / SAE
- 347 — Near S34700 / 1.4550: Nb-stabilized twin; Nb transfers through the arc so weld metal is also stabilized; slightly better creep. Interchangeable in most specs.
- 304H — Near Unstabilized high-carbon 304 for creep service; sensitizes but is cheaper — used where intergranular corrosion is not a concern.
- 304L — Functional Low-carbon route to weld stability; not suitable above ~425 °C for strength.
- 310 — Functional Stabilized 18-8 for service to ~870 °C; 310 takes over above that.
Superseded names for 321
- 1.4541 / X6CrNiTi18-10 — EN 10088: Older DIN name X10CrNiTi18 9; 1.4878 (X8CrNiTi18-10) is the heat-resisting version per EN 10095.
- S32100 / S32109 — UNS: 321 / 321H.
- 321S31 / 321S51 — BS 1449 / BS 970
- AMS 5510 / 5645 — SAE Aerospace: Sheet and bar specifications for aircraft exhaust and manifolds.
Key data for 321
Full composition, mechanical properties by thickness, heat treatment and applications for 321 →
Verified against ASTM A240/A240M-22. Last checked: September 2026.