We are Riddhi Siddhi Impex, a Mumbai-based Stainless Steel 347 Foils manufacturer and supplier, established in 2002. We slit niobium-stabilised austenitic foil to ASTM A240 / ASME SA-240 in thicknesses from 0.03 mm to 0.08 mm, with width held to ±0.1 mm tolerance. As an ISO 9001, 14001, and 45001 certified company, we keep ready stock, maintain a supply capacity of 400-500 tons monthly, and issue EN 10204 Type 3.1 / 3.2 mill test certificates on request.
Stainless Steel 347 foils are thin, flat-rolled sections of a niobium-stabilised austenitic grade. Niobium, added at ten times the carbon content minimum, ties carbon up as stable carbide, so weld zones keep their grain-boundary chromium and resist intergranular attack across the 427 to 816 °C sensitisation band. Fabricators reach for these stainless steel foils wherever the material must survive welding and heat. Stainless Steel 347 foils are typically used for thin-walled heat exchangers and high-temperature expansion joints.
As a reliable stainless steel 347 foil supplier, we slit every 347 stainless steel foil we offer in-house from the source coil. Material leaves annealed to ASTM A240, in any width from 3 mm to 2000 mm. Buyers choose BA, 2B, Matte, Matte PVC and Scotch-Brite surfaces, and our quality system follows each coil from inspection to dispatch.
As a specialised stainless steel 347 foil manufacturer, we provide ASTM A240 Type 347 foil in an annealed soft condition, with five surface finishes and four edge options, supplied in foil.
| Parameter | Details |
|---|---|
| Standard | ASTM A240 / ASME SA-240, AMS 5512 |
| Thickness | 0.03 mm to 0.08 mm |
| Width | 3 mm to 2000 mm |
| Width Tolerance | ±0.1 mm |
| Condition | Annealed (Soft) |
| Supply Forms | Cold rolled |
| Surface Finish | BA (Bright Annealed), 2B, Matte, Matte PVC, Scotch-Brite |
| Edge | Slit edge, Mill edge, Deburred edge, Round edge |
The defining addition is niobium at ten times the carbon minimum. It scavenges carbon into carbides, leaving the 17.00 to 19.00% chromium for corrosion duty.
| Element | Composition (% by weight) |
|---|---|
| Carbon (C) | 0.08 max |
| Manganese (Mn) | 2.00 max |
| Phosphorus (P) | 0.045 max |
| Sulphur (S) | 0.030 max |
| Silicon (Si) | 0.75 max |
| Chromium (Cr) | 17.00 to 19.00 |
| Nickel (Ni) | 9.00 to 13.00 |
| Niobium (Nb) | 10xC min, 1.00 max |
| Iron (Fe) | Balance |
Annealed SS 347 foil pairs 515 MPa minimum tensile strength with 40% elongation, so it stamps and folds cleanly. The grade isn't tempered; values below roughly 0.08 mm gauge are indicative.
| Property | Value (Annealed) |
|---|---|
|
Tensile Strength, minimum
|
515 MPa (75 ksi) |
|
Yield Strength (0.2% offset), minimum
|
205 MPa (30 ksi) |
|
Elongation in 50 mm, minimum
|
40% |
|
Hardness, maximum
|
201 HBW / 92 HRB |
Buyers ordering against a regional standard can cross-check UNS S34700 foil in the table below. Each 347 stainless steel foil we slit answers to every designation listed.
| Country / Standard | Designation |
|---|---|
| USA (UNS) | S34700 |
| Europe (EN) | X6CrNiNb18-10 |
| Germany (W.Nr) | 1.4550 |
| Japan (JIS) | SUS347 |
| China (GB) | 06Cr18Ni11Nb |
| Russia (GOST) | 08Х18Н12Б |
| France (AFNOR) | Z6CNNb18-10 |
| UK (BS) | 347S31 |
These 4 industries account for most of the SS 347 foil issued to Slit, deburred, or round edges are our lines. Buyers pick the grade for weld-zone stability, creep strength, and corrosion resistance under sustained heat.
Aerospace shops buy AMS 5512 foil for engine gaskets, heat shields, and exhaust ducting that cycle between ambient and red heat. Niobium stabilisation keeps weld seams corrosion resistant through repeated thermal swings, and thin gauges form tightly around collector rings without cracking.
Reactor liners, exchanger elements, and flange gaskets in hot oxidising service take most of the Alloy 347 foil this sector orders. Welded joints resist grain-boundary acid attack because the stabilised structure never surrenders its chromium.
Power plants fit Type 347 foil into furnace seals, boiler gaskets, and expansion bellows that flex under thermal cycling. Creep strength across the 427 to 816 °C band holds thin sections stable. Unstabilised grades sensitise in that window; however, 347 does not.
Hygienic equipment builders specify SS 347 foil for seals, diaphragms, and machine parts facing hot washdown cycles. The alloy withstands acidic and alkaline cleaning chemistry, and a smooth BA surface wipes clean between production runs.
Orders ship out from our Mumbai and Taloja locations in wooden cases or on pallets, with papers complete.
| Parameter | Details |
|---|---|
| Packaging | Wooden cases, pallet packing |
| Incoterms | FOB, CIF, CFR, EXW Mumbai |
| Dispatch Points | Mumbai and Taloja warehouses |
| Standard Lead Time | 4 to 5 days |
| Urgent Dispatch | 2 to 3 days |
| Payment Terms | Advance, credit, LC |
| Certification | EN 10204 Type 3.1 / 3.2 mill test certificates on request |
Stainless Steel 347 Foils price in India is roughly ₹315-750/kg, while export pricing is about $3.7 to $8.8 per kg depending on thickness, finish, and quantity. Nickel and niobium surcharges move the rate, along with gauge, slit width, finish, and quantity. Volume discounts apply, so call or WhatsApp us for the current rate.
We slit Stainless Steel 347 foil from 0.03 mm to 0.08 mm thick and to any width between 3 mm and 2000 mm, held to ±0.1 mm. Heavier flat-rolled material falls under our Stainless Steel 347 Coils range.
AISI 347 stainless steel alloy foil is covered by ASTM A240 / ASME SA-240 for flat-rolled products, with AMS 5512 applying to aerospace orders. EN 10204 Type 3.1 / 3.2 mill test certificates are available on request.
The difference between 347 foil and 321 foil lies in the stabiliser. Type 347 uses niobium while Type 321 uses titanium. Niobium carbides hold together at higher temperatures, so 347 foil keeps its weld-zone corrosion resistance longer in hot service.
Yes, we custom slit SS 347 foils to any width from 3 mm to 2000 mm on our in-house lines. Slit, mill, deburred, or round edges are available to suit winding and gasket work.
Available finishes for 347 stainless steel foils include BA (Bright Annealed), 2B, Matte, Matte PVC, and Scotch-Brite. All foils are supplied in cold rolled condition.
You can source Stainless Steel 347 Foils in India from us at Riddhi Siddhi Impex. Our Mumbai warehouse holds UNS S34700 foil ready for dispatch in 4 to 5 days, or 2 to 3 days when urgent. As a manufacturer, supplier, and exporter, we serve buyers across India and overseas. Phone or WhatsApp us; we will provide quotes within 24 hours.
