TP 904/L - 1.4539
Wst. 1.4539
UNS N08904
Stock program: 3 – 38 mm OD / 1/8” – 1.1/2” OD
Specification: ASTM A 269/A 213/A 1016 / ASME SB-677/NACE MR0175/PED 97/23 EC
Maximum service temperature: 450°C / 824°F
904L is a low carbon high alloy austenitic stainless steel, with chromium, nickel, molybdenum and copper contents, which is widely used in applications where the corrosion properties of 316L & 317L are not adequate. Although originally developed for greatly improved resistance to strong reducing acids (particularly sulphuric acid), it also has an very high resistance to a wide range of other environments. This feature has been verified to be very successful after many years of practical applications, which has resulted in 904L being standardized in many countries.
Characteristics
- The high Mo and the addition of copper to this grade give it greatly improved resistance to strong reducing acids, particularly sulphuric acid
- It is highly resistant to chloride attack, both pitting crevice corrosion and stress corrosion crashing
- Good machine ability and weldability
- The austenitic structure also gives this grade excellent toughness, even down to cryogenic temperatures
Market applications:
- Offshore, oil & gas
- Chemical processes
- Seawater cooling equipment
- Control and instrumentation
- Pharmaceutical
- Pulp and paper processing
Technical details
| Technical composition (%) | Fe | Cr | Ni | Mo | Mn | Cu | Si | P | N | C | S | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 904L | min | Bal. | 19.0 | 23.0 | 4.0 | - | 1.0 | 0.045 | - | - | - | - |
| max | - | 23.0 | 28.0 | 5.0 | 2.0 | 2.0 | 1.00 | 0.045 | 0.10 | 0.020 | 0.015 |
| Mechanical properties | 904L |
|---|---|
| Tensile strenght (mpa, min) | 490 - 700 |
| Yield strength (0.2% offset mpa, min) | 220 |
| Elongation (%, min) | 35 |
| Density / weight (g / cm3 / kg) | 8.05 |