SS 904L Stainless Steel
High-alloy super-austenitic grade with copper and molybdenum for sulphuric acid and severe chloride environments.
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What is SS 904L?
SS 904L (UNS N08904, EN 1.4539) is a super-austenitic stainless steel containing 19.0–23.0% chromium, 23.0–28.0% nickel and 4.0–5.0% molybdenum. High-alloy super-austenitic grade with copper and molybdenum for sulphuric acid and severe chloride environments. It is non-magnetic in the annealed condition, has a density of 7.95 g/cm³ and a minimum tensile strength of 490 MPa, and is used mainly for sulphuric and phosphoric acid plants, sea-water cooling and pulp bleaching.
- Type Super-austenitic
- Equivalents UNS N08904 · EN 1.4539 · SUS 890L
- Density 7.95 g/cm³
- Strength (min) 490 MPa tensile · 220 MPa yield
- Magnetic? Non-magnetic in the annealed condition
- Main uses Sulphuric and phosphoric acid plants, sea-water cooling, pulp bleaching
What is the chemical composition of SS 904L?
Typical ASTM A240 limits, % by weight (single values are maximums).
| C | Mn | Si | P | S | Cr | Ni | Mo | Cu | N |
|---|---|---|---|---|---|---|---|---|---|
| 0.020 max | 2.00 max | 1.00 max | 0.045 max | 0.035 max | 19.0 – 23.0 | 23.0 – 28.0 | 4.0 – 5.0 | 1.0 – 2.0 | 0.10 max |
What are the mechanical properties of SS 904L?
| Tensile strength (min) | 490 MPa |
|---|---|
| Yield strength 0.2% (min) | 220 MPa |
| Elongation (min) | 35% |
| Hardness (max) | 90 HRB max |
| Density | 7.95 g/cm³ |
What is the equivalent of SS 904L?
| ASTM / AISI | UNS | EN / W.Nr. | DIN | JIS |
|---|---|---|---|---|
| 904L | N08904 | 1.4539 | X1NiCrMoCu25-20-5 | SUS 890L |
Where is SS 904L used?
- Sulphuric and phosphoric acid plants
- Sea-water cooling
- Pulp bleaching
- Pharma and fine chemicals
Can SS 904L be welded?
Weldable with matching ER385 filler and low heat input. Clean welds thoroughly to keep full corrosion resistance.
Forming and machining
Forms well but needs more force than 316; machining is slower because the alloy is tough and work-hardens.
SS 904L sizes we supply
Sheets, plates, pipes and round bars — mostly supplied against specific orders for acid service.
SS 904L price compared with 304
Several times the price of 304 per kg, because of its 23–28% nickel, 4–5% molybdenum and copper. For today's rate, send us your size and quantity.
Our advice
904L costs much more than 316L but survives acids that would attack 316L quickly.
Values are typical ASTM A240 limits for flat products and are for guidance only. Always refer to the mill test certificate supplied with the material.
SS 904L — FAQs
What is the chemical composition of SS 904L?
SS 904L contains up to 0.020% carbon, up to 2.00% manganese, up to 1.00% silicon, up to 0.045% phosphorus, up to 0.035% sulphur, 19.0–23.0% chromium, 23.0–28.0% nickel, 4.0–5.0% molybdenum, 1.0–2.0% copper and up to 0.10% nitrogen, with the balance iron (typical ASTM A240 limits).
What is the equivalent of SS 904L?
SS 904L is UNS N08904, EN 1.4539 (X1NiCrMoCu25-20-5) and SUS 890L in the Japanese standard.
What is the density of SS 904L?
The density of SS 904L is about 7.95 g/cm³ (7950 kg/m³).
Where can I buy SS 904L in Vadodara?
Sagar Sales Corporation supplies SS 904L plate, pipe, flanges, 317l plate, 904l sheet in Vadodara with mill test certificates. Contact us for today's rate.
Get today's SS 904L rate
Tell us the grade, size, finish and quantity. We check stock and send a per-kg rate with dispatch date — usually the same working day.
- Rates direct from Vadodara stock
- Mill test certificate with every lot
- Cut-to-size and delivery all over India