904L is a high-alloy austenitic stainless steel intended for use under severe corrosive
conditions within the process industry. The grade is characterized by:
Very good resistance to attacks in acidic environments, e.g. sulphuric, phosphoric and acetic a cid
Very good resistance to pitting in neutral chloride-bearing solutions
Much better resistance to crevice corrosion than steels of the ASTM 304 and ASTM 316 types
Very good resistance to stress corrosion cracking
Good weldability
Standards
ASTM: TP904L
UNS: N08904
ISO: 4539-089-04-I
EN Number: 1.4539
EN Name: X1NiCrMoCu25-20-5
Pipe standard: ASTM A312, ASTM A269, ASTM B677, EN10216-5
Chemical Composition
C | Si | Mn | P | S | Cr | Ni | Mo | N | Cu |
≤0.020 | ≤0.50 | ≤2.00 | ≤0.030 | ≤0.010 | 24.0-26.0 | 19.0-21.0 | 6.0-7.0 | 0.15-0.25 | 0.5- 1.5 |
Physical properties
Density: 8.24 g/cm3
Thermal expansion1) |
Temperature ℃ | 20-100℃ | 20-200℃ | 20-300℃ |
Per ℃ | 15.0 x 10-6k-1 | 15.6 x 10-6k-1 | 16.1 x 10-6k-1 |
Mechanical properties
Status | Tensile Strength Min.(Mpa) | Yield Strength Min.(Mpa) | Elognation Min. % |
1100-1040℃ Annealed | 490 | 215 | 35 |
Application
904L are found in oil refineries and within the chemical and petrochemical industry. 904L is
also used within the pulp and paper industry, the mineral and metallurgical industry, the food
industry, in seawater cooling and in many other fields.
The grade is an excellent alternative to standard austenitic stainless steels in heat exchangers using high-temperature water with chloride contamination.
