Incoloy 800HT (Alloy 800HT), designated as UNS N08811 and W.Nr. 1.4959, is a high-temperature nickel-iron-chromium alloy engineered for excellent strength and oxidation resistance. It features enhanced creep and rupture properties, making it suitable for prolonged exposure to high heat and aggressive environments.
This alloy is commonly used in heat exchangers, furnace components, petrochemical piping, and thermal processing equipment. Incoloy 800HT performs reliably in applications involving temperatures above 600°C (1110°F) and resists carburization, sulfidation, and stress corrosion cracking.
| Nickel (Ni) | 30.0-35.0 % |
| Chromium (Cr) | 19.0-23.0 % |
| Iron (Fe) | 39.5 % min |
| Carbon (C) | 0.06-0.10 % |
| Manganese (Mn) | 1.50 % max |
| Sulfur (S) | 0.015 % max |
| Silicon (Si) | 1.0 % max |
| Copper (Cu) | 0.75 % max |
| Aluminum (Al) | 0.15-0.6 % |
| Titanium (Ti) | 0.15-0.6 % |
| Density | lb/in3 | 0.287 |
| g/cm3 | 7.94 | |
| Melting Rang | °F | 2475-2525 |
| °C | 1357-1385 | |
| Specific Heat, | (32-212°F), Btu/lb•°F | 0.11 |
| (0-100°C), J/kg•°C | 460 | |
| Permeability at 70°F (21°C) and 200 oersted (15 | 9 kA/m) | |
| Annealed | 1.014 | |
| Hot-Rolled | 1.009 | |
| Curie Temperature, | °F | -175 |
| °C | -115 |
|
Temperature |
Yield strength |
Tensile strength |
Elongation |
|||
|
Rp 0.2 |
Rm |
A |
||||
|
°C |
°F |
MPa |
Ksi |
MPa |
ksi |
% |
|
20 |
68 |
170 |
24.7 |
450-700 |
65.3-101.5 |
Longit. 35 Transverse 30 |
| Bar and Rod | Forgings | Seamless Pipe and Tube | Welded Pipe and Tube | Plate, Sheet, and Strip | Fittings |
| ASTM B 408 & ASME SB 408 | ASTM B 564 & ASME SB 564 | ASTM B 163/B 407 & ASME SB 163/ SB 407 | ASTM B 514/B 515 & ASME SB 514/ SB 515 | ASTM B 409 & ASME SB 409 | ASTM B 366/ASME SB 366 |
Standard product forms of Incoloy 800HT/Alloy 800HT/UNS N08811/W.Nr. 1.4959 are pipe, tube, sheet, strip, plate, round bar, flat bar, forging stock, hexagon and wire. The products are available in a wide variety of sizes. Please contact us at [email protected] for full information.
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