We are Riddhi Siddhi Impex, a Mumbai based supplier and stockist of Stainless Steel 439 Coils since 2002. We supply this titanium stabilised ferritic grade as per ASTM A240 / ASME SA-240, in thicknesses from 0.03 mm to 5 mm. Our ISO 9001, 14001 and 45001 certified facility holds ready stock, supplies 400 to 500 tonnes monthly, and provides EN 10204 Type 3.1 / 3.2 mill certificates.
Stainless Steel 439 coils are flat-rolled ferritic stainless steel, stabilised with titanium and holding 17 to 19% chromium. The grade is straight-chromium with almost no nickel, so it stays essentially immune to chloride stress corrosion cracking. Corrosion resistance runs close to Type 304 in many service environments, while thermal conductivity is higher. Buyers reach for 439 where oxidation resistance, formability, and weldability matter more than the broader acid resistance of austenitic grades. Stainless Steel 439 Coils are typically used in automotive exhaust systems and heat exchangers.
We maintain an extensive inventory of these stainless steel coils for immediate dispatch, sourcing from reputed primary mills and slitting to width in-house. Material ships in the annealed mill condition, in No.1, 2B, or BA finish, with mill or slit edges.
We provide ASTM A240 Type 439 coils in the annealed condition, across three surface finishes and edge options, slit to width from ready stock.
| Parameter | Details |
|---|---|
| Standard | ASTM A240 / ASME SA-240 |
| General Requirements | ASTM A480 |
| Thickness | 0.03 mm to 5 mm |
| Width | Up to 2000 mm |
| Width Tolerance | ±0.1 mm on narrow slit widths |
| Coil ID | 150 mm to 610 mm |
| Coil OD | Up to 1800 mm |
| Condition | Annealed (standard mill) |
| Surface Finish | No.1, 2B, BA (Bright Annealed) |
| Supply Form | Hot Rolled (HR), Cold Rolled (CR) |
| Edge | Mill edge, Slit edge |
Titanium defines this grade. It ties up carbon and nitrogen as stable carbonitrides, which keeps chromium in solution and gives 439 its weldability. Chromium at 17 to 19% carries the corrosion resistance, as the ASTM A240 composition below shows.
| Element | Composition (% by weight) |
|---|---|
| Carbon (C) | 0.030 max |
| Manganese (Mn) | 1.00 max |
| Phosphorus (P) | 0.040 max |
| Sulphur (S) | 0.030 max |
| Silicon (Si) | 1.00 max |
| Chromium (Cr) | 17.00 to 19.00 |
| Nickel (Ni) | 0.50 max |
| Titanium (Ti) | 0.20 + 4(C+N) min, 1.10 max |
| Aluminium (Al) | 0.15 max |
| Nitrogen (N) | 0.030 max |
| Iron (Fe) | Balance |
Annealed 439 stainless steel coils meet a minimum tensile strength of 415 MPa with 22% minimum elongation, so they draw, roll, and bend cleanly in routine forming. Coils ship in the standard mill condition only.
| Property | Value (Annealed) |
|---|---|
|
Tensile Strength, minimum
|
415 MPa (60 ksi) |
|
Yield Strength (0.2% offset), minimum
|
205 MPa (30 ksi) |
|
Elongation in 50.8 mm (2 in.), minimum
|
22% |
|
Hardness, maximum
|
89 HRB |
International buyers can cross-reference UNS S43035 coils against their regional standard below. The coils we stock correspond to the designations shown for cross-reference.
| Country / Standard | Designation |
|---|---|
| USA (UNS) | S43035 (AISI 439) |
| Europe (EN) | X3CrTi17 |
| Germany (W.Nr) | 1.4510 |
| Japan (JIS) | SUS 430LX |
| China (GB) | 022Cr18Ti |
| France (AFNOR) | Z4CT17 (legacy) |
| Russia (GOST) | 08Х17Т |
These are the applications that use the 439 ferritic stainless steel coils we supply. Buyers select the grade for oxidation resistance, high thermal conductivity, or resistance to chloride stress corrosion cracking.
Exhaust fabricators specify SS 439 coils for tubular manifolds, silencers, and catalytic converter housings. The titanium stabilisation lets welded joints hold corrosion resistance without a post-weld anneal. Higher chromium than Type 409 also raises the oxidation limit and improves resistance to exhaust condensate corrosion through heat cycling.
Residential furnace builders form primary heat exchangers from 439 coils because the grade moves heat well and resists thermal fatigue. The ferritic structure carries a lower thermal expansion than austenitic steel, so panels cycle between hot and cold with less distortion.
Food and beverage plants fit stainless steel 439 coils on storage vessels and conveyor panels where the surface must stay clean through repeated wash-downs. The grade withstands hot alkaline cleaning cycles, and it resists the chloride stress corrosion cracking that can attack austenitic grades in hot wash-down service.
Appliance and general fabrication shops press 439 coils into components that need a corrosion-resistant, weldable sheet at moderate cost. Domestic goods, sink units, and trim panels form cleanly from the annealed stock, and the ferritic structure's high plastic strain ratio gives deep-draw headroom.
Export orders leave Mumbai and Taloja, packed in wooden cases or on pallets.
| 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 standard; Type 3.2 on request |
Stainless Steel 439 Coils price in India is around ₹140 to ₹220 per kg, or roughly $1.6 to $2.6 per kg for international buyers. The rate tracks ferrochrome and global stainless benchmarks, and thickness, width, finish, and volume all affect the final price. Volume discounts apply to bulk orders, so call or WhatsApp us for today's rate.
SS 439 coils are available in thicknesses from 0.03 mm to 5 mm and widths up to 2000 mm. Coil ID runs from 150 mm to 610 mm, with coil OD up to 1800 mm. Custom widths are slit to ±0.1 mm on narrow widths.
The main difference between Stainless Steel 439 and Stainless Steel 304 coils is the structure and the nickel content. SS 439 is a ferritic grade with 17 to 19% chromium and almost no nickel, while SS 304 is austenitic with added nickel. SS 439 coils resist chloride stress corrosion cracking and cost less, though SS 304 holds broader resistance in acids.
Yes, SS 439 coils can be welded without post-weld annealing. The titanium stabilisation ties up carbon and nitrogen, so the weld zone keeps its ductility and doesn't lose intergranular corrosion resistance.
SS 439 coils carry higher chromium than SS 409, at 17 to 19% against roughly 11%. That gives 439 stronger corrosion and oxidation resistance than Type 409 can offer.
You can source 439 SS coils in India from us at Riddhi Siddhi Impex. We hold 439 coil in stock for immediate dispatch from our Mumbai warehouse. We are a supplier, stockist, and exporter, catering to buyers across India and abroad. Call or WhatsApp us and we quote within 24 hours.
