Incoloy 800H (UNS N08810 / W.Nr. 1.4958)
Incoloy 800H (UNS N08810 / W.Nr 1.4958) is an iron-nickel-chromium alloy having the same basic composition as Incoloy 800, with significantly higher creep rupture strength. The higher strength results from close control of carbon, aluminum and titanium contents in conjunction with a high temp anneal. The 800H modification was to control carbon (0.05 to 0.10%) and grain size to (>ASTM 5) to optimize stress rupture properties. Incoloy 800H has further modifications to the combined titanium and aluminum levels (0.85 to 1.2%) to ensure optimum high temperature properties.
Equivalent Grades
| Trademark | GB | GOST | ASTM | UNS | DIN | W.Nr. | NF | BS | JIS | SS |
| Incoloy 800H | NS1102
NS112 | – | Incoloy 800H | N08810 | X10NiCrAlTi32-20 | 1.4958 | – | NA15H | – | – |
Chemical Composition, %
| Alloy | C | Si | Mn | P | S | Cr | Ni | Al+Ti | Ti | Fe |
| Incoloy 800H | 0.05-0.10 | ≤0.10 | ≤3.00 | ≤0.03 | ≤0.02 | 19.0-23.0 | 30.0-35.0 | 0.30-1.20 | 0.15-0.60 | ≥39.5 |
Typical Physical and Mechanical Properties (RT, Solution annealed)
| Density, g/cm3 | Melting Point, ℃ | Tensile Strength, MPa | Yield Strength, MPa | ELongation, % | Hardness, HB |
| 8.00 | 1357-1375 | 531 | 200 | 52 | – |
Available Products and Specifications
| Rod, Bar, Wire and Forgings | ASTM B408/ASME SB408, ASTM B564/ASME SB564, ISO 9723/9724/9725 |
| Plate, Sheet and Strip | ASTM A240/A480/B409/B906/ASME SA240/SA480/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
- Resistance to prolonged exposure to elevated temperatures
- Excellent resistance to oxidation, sulfidation, and carburization
- Added Carbon and annealing treatment allows for higher creep and rupture properties above 600℃
- Resistant to high temperature corrosion
- Readily machined by standard methods
- Best joined/welded using products for high temperature situations
- Resistance to aqueous corrosion at moderate temperatures
Applications
- Chemical and Petrochemical Processing—process equipment for the production of ethylene, ethylene dichloride, acetic anhydride, ketene, nitric acid and oxy-alcohol
- Petroleum Refining—steam/hydrocarbon reformers and hydrodealkylation units
- Power Generation—steam super-heaters and high temperature heat exchangers in gas-cooled nuclear reactors, heat exchangers and piping systems in coal-fired power plants
- Thermal Processing Fixtures—radiant tubes, muffles, retorts and fixtures for heat-treating furnaces
