We are Riddhi Siddhi Impex, a Mumbai-based supplier and stockist of Stainless Steel 439 Sheets & Plates, established in 2002. We stock this titanium-stabilised ferritic grade to ASTM A240 / ASME SA-240 in sheets from 3.8 mm and heavier plates. As an ISO 9001, 14001, and 45001 certified company, we have a monthly supply capacity of 400 to 500 tonnes and export to more than 60 countries.
439 Stainless Steel sheets and plates are flat-rolled ferritic stainless steel holding 17 to 19% chromium with a titanium addition. Titanium ties up carbon and nitrogen, so welded joints keep their intergranular corrosion resistance without a post-weld anneal. The grade carries almost no nickel, so it resists chloride stress corrosion cracking, and its corrosion resistance runs close to that of Type 304. These Stainless Steel Sheets and Plates are used in domestic appliances, heat exchangers, and automotive applications.
Our warehouse carries UNS S43035 flat products sourced from reputed primary mills: cold-rolled sheet from 3.8 mm and hot-rolled plate up to 2000 mm wide. Every lot ships annealed, with EN 10204 Type 3.1 / 3.2 mill test certificates on request.
We provide ASTM A240 Type 439 sheets and plates ex-stock in the annealed mill condition, with a choice of surface finishes. Custom widths are slit to a ±0.1 mm tolerance
| Parameter | Details |
|---|---|
| Standard | ASTM A240 / ASME SA-240 |
| Thickness (Sheets) | 3.8 mm to 6 mm |
| Thickness (Plates) | Above 6 mm, up to 10 mm |
| Width | Up to 2000 mm |
| Width Tolerance | ±0.1 mm |
| Condition | Annealed (standard mill) |
| Surface Finish | 2B, BA (Bright Annealed), No.1 (annealed and pickled) |
| Supply Forms | Hot rolled and Cold rolled |
| Edge | Mill edge, Slit edge |
| Form | Cold Rolled Sheets, Hot Rolled Plates |
Titanium is the key element. A minimum of 0.20 + 4(C+N) locks carbon into stable carbonitrides, leaving the 17 to 19% chromium free to fight corrosion.
| 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 |
| Nitrogen (N) | 0.030 max |
| Iron (Fe) | Balance |
Annealed Grade 439 stainless steel reaches a minimum tensile strength of 415 MPa, and 22% elongation leaves room for pressing and roll forming. Material ships in the soft mill condition.
| Property | Value (Annealed) |
|---|---|
|
Tensile Strength, minimum
|
415 MPa (60 ksi) |
|
Yield Strength (0.2% offset), minimum
|
205 MPa (30 ksi) |
|
Elongation in 50 mm, minimum
|
22% |
|
Hardness, maximum
|
89 HRB |
International buyers can match SS 439 sheets and plates against their regional standard below. Every designation covers the same 18Cr-Ti ferritic chemistry.
| Country / Standard | Designation |
|---|---|
| USA (UNS) | S43035 |
| Europe (EN) | X3CrTi17 |
| Germany (W.Nr) | 1.4510 |
| Japan (JIS) | SUS430LX |
| China (GB) | 022Cr18Ti |
These 5 industries widely specify the Type 439 SS sheets and plates we dispatch. Buyers pick the grade for oxidation resistance, weldable seams, and freedom from chloride stress corrosion cracking.
Manifold shells, muffler bodies, and converter housings come off Type 439 sheet because welded seams survive hot exhaust condensate. Chromium above the Type 409 level raises the oxidation ceiling, and the low thermal expansion of the ferritic structure means less distortion through repeated heat cycles than an austenitic grade would show.
Ferritic 439 plate moves heat faster than austenitic alternatives while expanding less. Builders of condensers and residential heat exchangers weld tube plates and shells from the grade, and the stabilised chemistry keeps each joint resistant to intergranular attack.
Sinks, splashbacks, and food-contact surfaces require a sheet that stays sound through daily wash-downs. SS 439 stands up to hot alkaline cleaning and routine chloride-bearing rinse water better than unstabilised 430, so processing lines gain hygienic surfaces at a cost below nickel-bearing grades. For heavy or continuous chloride exposure, 316L remains the safer choice.
Interior cladding, lift trim, and column covers are pressed from Grade 439 SS sheets in 2B or BA finish. The bright surface holds its appearance indoors, and fabricators bend and weld panels without post-weld treatment.
Appliance producers draw washing machine drums, oven liners, and dishwasher panels from annealed 439 sheet. The 22% minimum elongation gives deep-drawing headroom, and the magnetic ferritic base also suits induction-compatible cookware bodies.
Orders leave from our Mumbai and Taloja warehouses in export-grade packing for sea freight.
| 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 on request |
Stainless Steel 439 Sheets & Plates price in India sits around ₹130 to ₹220 per kg, roughly $1.4-$2.3 per kg for export buyers. The figures are indicative; the market moves with ferrochrome and stainless benchmarks, while thickness, finish, and volume shift the final rate. Call or WhatsApp us for today's price.
The difference between SS 439 and SS 430 sheets and plates is the titanium addition. Titanium stops sensitisation during welding, so 439 suits welded fabrication, while unstabilised 430 stays better in unwelded work.
Yes, 439 Stainless Steel Sheets & Plates can be welded by standard fusion methods. The stabilised chemistry protects the weld zone from intergranular corrosion, and post-weld annealing is generally not required.
We stock SS 439 sheets from 3.8 mm to 6 mm and plates from above 6 mm up to 10 mm, in widths up to 2000 mm. Custom widths are slit to ±0.1 mm.
SS 439 sheets and plates are covered by ASTM A240 / ASME SA-240, with general flat-product requirements under ASTM A480.
Yes, we provide EN 10204 Type 3.1 / 3.2 mill test certificates on request with every consignment of SS 439 sheets and plates.
You can source 439 Stainless Steel Sheets & Plates in India from us at Riddhi Siddhi Impex. Our Mumbai warehouse holds Type 439 flat stock ready for dispatch in 4 to 5 days. As a supplier, stockist, and exporter, we serve buyers across India and overseas. Phone or WhatsApp us, and get a quote within 24 hours.
