904L (UNS N08904) is a high-nickel, high-molybdenum copper-bearing superaustenitic stainless with PREN around 36. It far outperforms 316L in dilute sulphuric and phosphoric acid and chloride media, with markedly better stress-corrosion-cracking resistance.
As a manufacturer and global exporter of special alloys since 2012, Shanghai Hangbo Alloy Group Co., Ltd. supplies Stainless Steel 904L as round bars (φ2–600 mm, up to 12 m), plates & sheets (0.5–100 mm thick, up to 2500 mm wide), seamless tubes & pipes (φ6–630 mm OD, 0.5–40 mm wall), flanges & pipe fittings (Class 150–2500, DN15–DN1200), forgings & rolled rings (up to 7500 kg, 3500 mm OD) — all with EN 10204 3.1 certified material test reports.
Stainless Steel 904L Chemical Composition (wt%)
| Element | Content (wt%) | Element | Content (wt%) |
|---|---|---|---|
| Fe (铁) | Balance | Cu (铜) | 1.00–2.00 |
| Ni (镍) | 23.0–28.0 | Mn (锰) | ≤ 2.00 |
| Cr (铬) | 19.0–23.0 | Si (硅) | ≤ 1.00 |
| Mo (钼) | 4.00–5.00 | C (碳) | ≤ 0.020 |
Stainless Steel 904L Mechanical Properties
| Property | Value |
|---|---|
| Tensile strength (Rm) | ≥ 490 MPa |
| Yield strength (Rp0.2) | ≥ 220 MPa |
| Elongation (A) | ≥ 35 % |
| Hardness | ≤ 200 HB |
| Density | 8.00 g/cm³ |
| Melting range | 1300–1390 °C |
| Thermal conductivity | 12.0 W/m·K |
| Young's modulus | 195 GPa |
| Max service temperature | 400 °C |
Key Advantages
- PREN around 36 — roughly 1.4 times the pitting resistance of 316L
- Copper markedly improves dilute sulphuric acid resistance
- High nickel (23–28%) resists stress-corrosion cracking
- Weldable with no post-weld heat treatment required
Relevant Standards
- ASTM B649
- ASTM B625
- ASTM B673
- ASTM A240
- UNS N08904
Typical Applications
- Sulphuric and phosphoric acid plant
- Fertiliser and phosphate chemical units
- Seawater cooling and desalination
- Pulp, paper and pickling equipment
- Pharmaceutical and fine-chemical vessels
Why Buy from Hangbo Alloy?
- Factory-direct manufacturer — founded 2012, headquartered in Shanghai Qingpu
- Full product range — bar, plate, sheet, strip, tube, forging, welding wire, flanges and machined parts
- Certified quality — ISO 9001:2015, GB/T 19001-2016, GJB 9001C-2017, EN 10204 3.1 mill test certificates with third-party inspection (SGS / BV / TUV) available on request
- Complete mill documentation — chemical analysis, mechanical test, ultrasonic test (UT), hardness and grain-size reports with every shipment
Contact Us — Shanghai Hangbo Alloy Group Co., Ltd.
Shanghai Hangbo Alloy Group Co., Ltd.
📍 No. 388 Songhuang Road, Qingpu District, Shanghai, China
📞 Tel / WhatsApp: +86 15618279078
✉️ Email: demi@nickel-alloy.com
🕒 Available 24 hours a day, 7 days a week — enquiries answered around the clock.
Send your drawing or enquiry (grade, form, size, quantity, standard) for a same-day quotation.
Frequently asked questions
How does 904L compare economically with 316L?
904L costs roughly 3–5 times 316L per kilogram but typically lasts several times longer in dilute sulphuric acid, phosphoric acid and chloride service. Where downtime is expensive and the medium aggressive, 904L has the lower life-cycle cost; for mild media such as clean water, steam or food-grade duties, 316L is more economical.
What forms and sizes are available?
We supply Stainless Steel 904L as round bars (φ2–600 mm, up to 12 m), plates & sheets (0.5–100 mm thick, up to 2500 mm wide), seamless tubes & pipes (φ6–630 mm OD, 0.5–40 mm wall), flanges & pipe fittings (Class 150–2500, DN15–DN1200), forgings & rolled rings (up to 7500 kg, 3500 mm OD). Custom lengths, tolerances and machining to drawing are available on request.
What is the MOQ and lead time?
MOQ is flexible — trial orders from a single piece are welcome. Stock sizes ship in 3–7 days; custom forgings and machined parts typically 15–35 days depending on quantity and process.
Can you provide third-party inspection and shipping to my port?
Yes. SGS / BV / TUV or your nominated inspector can witness all tests before shipment. Full export documentation is provided, and we ship worldwide by sea or air on FOB, CIF or DDP terms.