ASME SB677, ASTM B677 TP904L (UNS N08904) Stainless Steel Seamless Pipe
ASME SB677, ASTM B677 TP904L (UNS N08904) Stainless Steel Seamless Pipe
TP904L is a non-stabilised low carbon high alloy austenitic stainless steel. The addition of copper to this grade gives it greatly improved resistance to strong reducing acids, particularly sulphuric acid. It is also highly resistant to chloride attack - both pitting / crevice corrosion and stress corrosion cracking. This grade is non-magnetic in all conditions and has excellent weldability and formability. The austenitic structure also gives this grade excellent toughness, even down to cryogenic temperatures. 904L does have very substantial contents of the high cost ingredients nickel and molybdenum. Many of the applications in which this grade has previously performed well can now be fulfilled at lower cost by duplex stainless steel 2205 (S31803 or S32205), so it is used less commonly than in the past.
Chemical Composition:
Grade |
C | Mn | Si | P | S | Cr | Mo | Ni | Cu | |
| TP904L | min. max. |
- 0.020 |
- 2.00 |
- 1.00 |
- 0.045 |
- 0.035 |
19.0 23.0 |
4.0 5.0 |
23.0 28.0 |
1.0 2.0 |
Mechanical Properties:
Grade |
Tensile Strength (MPa) min | Yield Strength 0.2% Proof (MPa) min | Elongation (% in 50mm) min | Hardness | |
| Rockwell B (HR B) | Brinell (HB) | ||||
| 904L | 490 | 220 | 35 | 70-90 typical | - |
| Rockwell Hardness value range is typical only; other values are specified limits. | |||||
Physical Properties:
Grade |
Density (kg/m3) |
Elastic Modulus (GPa) |
Mean Co-eff of Thermal Expansion (m/m/C) | Thermal Conductivity (W/m.K) |
Specific Heat 0-100C (J/kg.K) |
Elec Resistivity (n.m) |
|||
| 0-100C | 0-315C | 0-538C | At 20C | At 500C | |||||
| TP904L | 8000 | 200 | 15 | - | - | 13 | - | 500 | 850 |
Grade Specifications:
Grade |
UNS No | Old British | Euronorm | Swedish SS | Japanese JIS | ||
| BS | En | No | Name | ||||
| TP904L | N08904 | 904S13 | - | 1.4539 | X1NiCrMoCuN25-20-5 | 2562 | - |
| These comparisons are approximate only. The list is intended as a comparison of functionally similar materials not as a schedule of contractual equivalents. If exact equivalents are needed original specifications must be consulted. | |||||||
Possible Alternative Grades:
| Grade | Why it might be chosen instead of 904L |
| 316L | A lower cost alternative, but with much lower corrosion resistance. |
| 6Mo | A higher resistance to pitting and crevice corrosion resistance is needed. |
| 2205 | A very similar corrosion resistance, with the 2205 having higher mechanical strength, and at a lower cost to 904L. (2205 not suitable for temperatures above 300C.) |
| Super duplex | Higher corrosion resistance is needed, together with a higher strength than 904L. |
Applications:
- Typical applications include
- Processing plant for sulphuric, phosphoric and acetic acids
- Pulp and paper processing
- Components in gas scrubbing plants
- Seawater cooling equipment
- Oil refinery components
- Wires in electrostatic precipitators
Get in Touch
Have questions about our products or want to discuss a custom order? Our team is ready to help you.