Niobium-Stabilized Austenitic Grade · Exceptional Resistance to Intergranular Corrosion · Superior High-Temperature Service · Global Industrial Supply
347 and 347H stainless steel plates are niobium-stabilized austenitic stainless steels designed for high-temperature service and resistance to intergranular corrosion. The addition of niobium (columbium) helps stabilize the material, preventing carbide precipitation during welding and heating processes. 347H is a high-carbon version of 347 stainless steel, offering improved creep resistance and higher strength at elevated temperatures.
HRS Ferritic is a trusted and leading 347/347h stainless steel Plate Supplier, Stockist, and Importer, delivering high-quality plates sourced from certified global mills for reliable performance in critical applications.
The mechanism of 347/347H plates is based on niobium stabilization, which prevents chromium depletion at grain boundaries to retain corrosion resistance at high temperatures.
ASTM A240 · ASME SA240 · UNS S34700/S34709 · EN 1.4550/1.4961
| Specification | Details |
|---|---|
| ASTM / ASME | ASTM A240 / ASME SA240 (Plate, Sheet, and Strip) |
| UNS | UNS S34700 / UNS S34709 |
| EN / DIN | 1.4550 (X6CrNiNb18-10) / 1.4961 (X6CrNiNb18-11) |
| ISO | ISO X6CrNiNb18-10 / ISO X6CrNiNb18-11 |
| JIS | SUS 347 / SUS 347H |
| Product Form | Sheets / Plates |
| Thickness Range | 0.5 mm to 100 mm |
| Standard Widths | 1000, 1219, 1250, 1500, 1800, 2000, 2500, 3000, 3500 mm |
| Standard Lengths | 2000, 2440, 2500, 3000, 5800, 6000 mm |
| Processing | Custom Width and Length Cut Available |
| Surface Finish | Hot Rolled (HR), Cold Rolled (CR), Annealed & Pickled (AP) |
| Supply Condition | Solution Annealed |
| Packaging | Bundled, Wooden Plates, Bubble wraps, Customized |
Precision sheets, heavy plates, and high-temperature shim sheets available.
Slitting coils, perforated coils, and thin foils from 0.05 mm thickness.
Circles, rings, custom-cut blanks, and chequered (tread) plates in stock.
Mill edge, slit edge, round edge, and square edge available as per order.
17.0–19.0% — Core element for oxide layer formation.
≥ 10 × C — Stabilizes alloy and prevents carbide precipitation.
0.04–0.10% (347H) — Higher content for improved high-heat strength.
9.0–13.0% — Enhances ductility and toughness in austenitic structure.
≥ 515 MPa — High ultimate strength for critical service.
≥ 205 MPa — Reliable structural stability at 0.2% offset.
≥ 40% — Exceptional ductility in 50 mm gauge length.
≤ 201 HB — Controlled hardness for high-temp pressure service.
We supply diverse variations of 347/347H plates processed for specific industrial surface and heat requirements.
Niobium stabilization prevents intergranular corrosion by ensuring chromium remains available for the protective oxide layer.
| Element | 347 (% max/min) | 347H (% max/min) |
|---|---|---|
| Carbon (C) | ≤ 0.08 | 0.04 – 0.10 |
| Chromium (Cr) | 17.0 – 19.0 | 17.0 – 19.0 |
| Nickel (Ni) | 9.0 – 13.0 | 9.0 – 13.0 |
| Niobium (Nb) + Ta | ≥ 10 × C (min), ≤ 1.0 | Same as 347 |
| Manganese (Mn) | ≤ 2.0 | ≤ 2.0 |
| Silicon (Si) | ≤ 1.0 | ≤ 1.0 |
| Phosphorus (P) | ≤ 0.045 | ≤ 0.045 |
| Sulfur (S) | ≤ 0.030 | ≤ 0.030 |
| Iron (Fe) | Balance | Balance |
Grade 347/347H is internationally recognized for its niobium-stabilized high-heat performance.
| Standard / Organization | 347 Grade | 347H Grade |
|---|---|---|
| ASTM / ASME | 347 (UNS S34700) | 347H (UNS S34709) |
| AISI / UNS | AISI 347 / S34700 | AISI 347H / S34709 |
| EN (Europe) | 1.4550 (X6CrNiNb18-10) | 1.4961 (X6CrNiNb18-11) |
| DIN (Germany) | 1.4550 | 1.4961 |
| ISO | X6CrNiNb18-10 | X6CrNiNb18-11 |
| JIS (Japan) | SUS 347 | SUS 347H |
| BS (UK) | 347S31 | 347S51 |
| AFNOR (France) | Z6CNNb18-10 | Z10CNNb18-10 |
| GOST (Russia) | 08Kh18N12B | 08Kh18N12B (High C) |
| UNI (Italy) | X6CrNiNb18-10 | X8CrNiNb16-13 |
| SS (Sweden) | 2338 | 2368 |
| KS (Korea) | STS 347 | STS 347H |
| IS (India) | 04Cr18Ni10Nb | 06Cr18Ni11Nb |
HRS Ferritic is dedicated to delivering high-performance stainless steel products with a focus on quality, reliability, and customer satisfaction. We are recognized as a premier Supplier, Stockist, and Importer, ensuring every plate is sourced from valuable certified mills and conforms to the highest engineering standards.
Quick answers to common queries about 347/347H Stainless Steel Plate.