This Nickel-Chromium-Iron alloy has the same basic composition as Incoloy 800, but has significantly higher creep rupture strength, resultant from the close control of the carbon, aluminium and titanium contents. It has good strength and excellent resistance to oxidation and carburisation in high temperature atmospheres. It also resists corrosion in many aqueous environments.
Incoloy® 800HT is also known as Nicrofer 3220 HP.
| Element | Min % | Max % |
| Ni | 30.00 | 35.00 |
| Co | – | 2.00 |
| Cu | – | 0.75 |
| Cr | 19.00 | 23.00 |
| Al | 0.15 | 0.60 |
| C | 0.05 | 0.10 |
| Si | – | 1.00 |
| Mn | – | 1.50 |
| Ti | 0.15 | 0.60 |
| Fe | bal | |
| S | – | 0.015 |
Density
7.94 g/cm³ | 0.287 lb/in³
Melting Point
1385°C | 2525°F
Coefficient of Expansion
14.4 μm/m °C (20 – 100°C) | 7.9 x 10-6 in/in °F (70 – 212°F)
Modulus of Rigidity
78.9 kN/mm² | 11444 ksi
Modulus of Elasticity
196.5 kN/mm² | 28500 ksi
Heat Treatment of Finished Parts
| Condition as supplied by Alloy Wire | Type | Temperature | Time (Hr) | Cooling | |
| °C | °F | ||||
| Annealed or Spring Temper | Stress Relieve | 450 – 470 | 840 – 880 | 0.5 – 1 | Air |
Properties
| Condition | Approx. tensile strength | Approx. operating temperature | ||
| N/mm² | ksi | °C | °F | |
| Annealed | 600 – 800 | 87 – 116 | -200 to +1000 | -330 to +1830 |
| Spring Temper | 800 – 1100 | 116 – 159 | -200 to +1000 | -330 to +1830 |