Incoloy 825 (UNS N08825/ W.Nr. 2.4858)
Incoloy 825 (UNS N08825 / W.Nr. 2.4858) is a Ni-Fe-Cr-Mo Ti-stabilized alloy with excellent resistance to sulfuric and phosphoric acids. Resistant to reducing and oxidizing acids, pitting, stress-corrosion cracking and intergranular corrosion, it is used in chemical and petrochemical processing, oil and gas extraction, pollution control, waste processing and pickling applications.
Equivalent Grades
| Trademark | GB | GOST | ASTM | UNS | DIN | W.Nr. | NF | BS | JIS | SS |
| Incoloy 825 | GH1140
NS1402 | ЭИ602 | Incoloy 825 | N08825 | NiCr21Mo | 2.4858 | – | NA16 | NCF 825 | – |
Chemical Composition, %
| Alloy | C | Si | Mn | P | S | Cr | Ni | Mo | Al | Ti | Cu | Fe |
| Incoloy 825 | ≤0.05 | ≤0.50 | ≤1.00 | ≤0.03 | ≤0.03 | 19.5-23.5 | 38.0-46.0 | 2.5-3.5 | ≤0.20 | 0.6-1.2 | 1.5-3.0 | ≥22,0 |
Typical Physical and Mechanical Properties (RT, Solution annealed)
| Density, g/cm3 | Melting Point, ℃ | Tensile Strength, MPa | Yield Strength, MPa | ELongation, % | Hardness, HB |
| 8.14 | 1370-1400 | 690 | 310 | 45 | – |
Available Products and Specifications
| Rod, Bar, Wire and Forgings | ASTM B425/ASME SB425, ASTM B564/ASME SB564, ISO 9723/9724/9725, DIN 17752/17753/17754 |
| Plate, Sheet and Strip | ASTM B424/B409/B906/ASME SB424/SB409/SB906, ISO 6208 |
| Pipe and Tube | ASTM B163/ASME SB163, ASTM B407/B829/ASME SB407/SB829, ASTM B514/B775/ASME SB514/SB775, ASTM B515/B751/ASME SB515/SB751, ISO 6207 |
| Welding Product | – |
| Others | ASTM B366/ASME SB366(Fittings) |
Features
- Good resistance to stress-corrosion cracking
- Satisfactory resistance to pitting and crevice corrosion
- Good resistance to oxidizing and non-oxidizing hot acids
- Good mechanical properties at both room and elevated temperatures, up to approximately 550℃
- Approval for pressure vessels with wall temperatures up to 450℃
Applications
- Components such as heating coils, tanks, crates, baskets and chains in sulphuric acid pickling plants
- Sea-water-cooled heat exchangers, offshore product piping systems; tubes and components in sour gas service
- Heat exchangers, evaporators, scrubbers, dip pipes etc. in phosphoric acid production
- Air-cooled heat exchangers in petroleum refineries
- Food processing
- Chemical plant
