800/800H/800HT
Wst. 1.4876/1.4958/1.4959
UNS N08800/N08810/N08811
Stock program: Available on request
Specification: ASTM B 407 / ASTM B 163 / ASME SB-163 / EN ISO 1127/96/NACE MR0175
Maximum service temperature: 1100°C/2000°F
Alloy 800, 800H and 800HT are nickel-iron-chromium alloys with good strength and excellent resistance to carburization and oxidation in high temperature environment. Alloy 800 was the first alloy with analyses similar to those of alloy 800H and 800HT, except the higher level of carbon in 800H/HT and the addition of aluminum in 800H and titanium in 800HT. The modification of alloy 800 into alloy 800H was performed to control carbon percentage and grain size to optimize stress rapture properties. Alloy 800 is primarily used for temperatures up to 600°C / 1100°F and the alloys 800H/800HT are commonly used for temperature above. To ensure optimal high temperature properties the nickel alloy is dual certified as 800H/800HT and combines the properties of both forms.
Characteristics
- Excellent resistance to high temperature corrosion
- Super creep and rapture strength during extended high temperature exposure
- Stable metallurgical structure by long term exposure at high temperatures
- Good corrosion resistance in many acidic environments
- Very good resistance to sulfur-containing atmospheres
- High resistance to chloride stress corrosion
Market applications:
- Chemical processing
- Oil & gas
- Heat treating equipment
- Nuclear power plants
- Pulp & paper industry
Technical details
| Technical composition (%) | Cr | Ni | Mn | Cu | Si | C | S | Ti | Al | Bal. | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 800 | min | 19.0 | 30.0 | - | - | - | - | - | 0.15 | 0.15 | 39.5 |
| max | 23.0 | 35.0 | 1.50 | 0.75 | 1.0 | 0.100 | 0.015 | 0.60 | 0.60 | - | |
| 800H | min | 19.0 | 30.0 | - | - | - | 0.050 | - | 0.25 | 0.25 | 39.5 |
| max | 23.0 | 35.0 | 1.50 | 0.75 | 1.0 | 0.100 | 0.015 | 0.60 | 0.60 | - | |
| 800HT | min | 19.0 | 30.0 | - | - | - | 0.060 | - | 0.25 | 0.25 | 39.5 |
| max | 23.0 | 35.0 | 1.50 | 0.75 | 1.0 | 0.100 | 0.015 | 0.60 | 0.60 | - |
| Mechanical properties | 800 | 800H | 800HT |
|---|---|---|---|
| Tensile strenght (mpa, min) | 536 | 448 | 448 |
| Yield strength (0.2% offset mpa, min) | 150 | 172 | 172 |
| Elongation (%, min) | 20 | 20 | 20 |
| Density / weight (g / cm3 / kg) | 7.94 | 7.94 | 7.94 |