ASTM A182 F304H — Chemical Composition & Mechanical Properties
ASTM A182 F304H is a austenitic stainless steel grade for forged flanges & fittings (UNS S30409, EN / W.Nr 1.4948). This sheet summarises its chemical composition limits, minimum mechanical properties, heat treatment and typical service. Teshi Group manufactures flanges and fittings in this grade.
ASTM A182 F304H at a glance
| Specification | ASTM A182 F304H |
|---|---|
| Material family | Austenitic stainless steel |
| Product form | Forged flanges & fittings |
| UNS number | S30409 |
| EN / W.Nr equivalent | 1.4948 |
| Also known as | 304H |
| PREN (min values) | 18.0 |
| Document | TG-MG-047 · Rev. 1 · October 2026 |
Typical service
High-temperature service above about 525 °C — superheater headers, refinery heaters
Heat treatment
Solution annealed 1040 °C min, rapid cool (H grades: grain size ASTM No. 6 or coarser)
Chemical composition of ASTM A182 F304H (weight %)
Single values are maximums unless shown as a range or “min”.
Mechanical properties
| Tensile strength, min | 515 MPa |
|---|---|
| Yield strength (0.2 % offset), min | 205 MPa |
| Elongation, min | 30 % |
| Hardness | Not specified |
About austenitic stainless steel
Austenitic stainless steels are iron–chromium–nickel alloys with 16–26 % chromium and 8–22 % nickel. Nickel keeps the structure austenitic (face-centred cubic), which makes these steels non-magnetic when annealed, very tough down to cryogenic temperatures, and easy to form and weld.
Reference information compiled from the published standard for convenience. It does not replace the current edition of the governing standard, which takes precedence. Verify critical dimensions and properties before design, purchase or fabrication. Teshi Engineers & Sales Promoters (P) Ltd accepts no liability for errors or omissions.
International equivalents of ASTM A182 F304H
All equivalents| Standard system | Nearest equivalent grade |
|---|---|
| USA — ASTM / ASME | ASTM A182 F304H · ASME SA-182 F304H |
| USA — UNS | S30409 |
| Europe — EN designation | X6CrNi18-10 |
| Europe — W.Nr | 1.4948 |
| Japan — JIS | SUS304HTB / SUSF304H |
| China — GB / NB | S30409 (07Cr19Ni10) |
| China — old GB designation | 1Cr18Ni9 |
| UK — BS (withdrawn) | 304S51 |
Equivalents are the nearest commonly cited grades. Chemistry, mechanical properties and testing differ between standards — compare them before substituting one for another.
Same alloy in other product forms
| Product form | Specification / grade |
|---|---|
| Seamless & welded pipe | ASTM A312 TP304H |
Standards for ASTM A182 F304H
All material standardsFAQ
ASTM A182 F304H: common questions
What is the minimum yield strength of ASTM A182 F304H?
205 MPa, with a minimum tensile strength of 515 MPa.
What is the carbon content of ASTM A182 F304H?
0.04–0.10 %.
What is the PREN of ASTM A182 F304H?
About 18, calculated as Cr + 3.3Mo + 16N using the specification minimum values. Typical heats are a little higher.
What is the UNS number and EN equivalent of ASTM A182 F304H?
UNS S30409; the nearest European designation is W.Nr 1.4948. Equivalents are close but not identical — check the specification if substituting.
How is ASTM A182 F304H heat treated?
Solution annealed 1040 °C min, rapid cool (H grades: grain size ASTM No. 6 or coarser).
What is the Chinese (GB) equivalent of ASTM A182 F304H?
The nearest Chinese equivalent is S30409 (07Cr19Ni10), formerly 1Cr18Ni9. Equivalents are close but not identical — compare chemistry and properties before substituting.
What is the JIS equivalent of ASTM A182 F304H?
The nearest Japanese (JIS) equivalent is SUS304HTB / SUSF304H.
Does Teshi Group supply ASTM A182 F304H?
Teshi Group manufactures flanges and fittings in this grade. Send your size, rating and quantity to info@teshigroup.com for a quotation with EN 10204 3.1 certificates.
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