Incoloy 800HT^* Specification
*Trade name of Special Metals Group of Companies

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.

Good Mechanical Properties at Elevated Temperatures	No
Corrosion Resistant at Ambient Temperatures	Yes
Corrosion Resistant & Good Mechanical Properties at Elevated Temperatures	No
Oxidation Resistant	Yes
Precipitation Hardenable	No

Approximate Chemical Composition
Ni	30 - 35%
Fe	39.5% min
Cr	19 - 23%
C	0.06 - 0.1%
Al	0.15 - 0.6%
Ti	0.15 - 0.6%
Al + Ti	0.85 - 1.2%

Properties
DENSITY	7.94 g/cm3	0.287 lb/in3
MELTING POINT	1385 oC	2525 oF
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

CONDITION OF SUPPLY	HEAT TREATMENT (AFTER FORMING)
Annealed/Spring Temper	Stress relieve at 450 - 470oC (840 - 880oF) for 30 - 60 minutes and air cool.

CONDITION	APPROX TENSILE STRENGTH		APPROX SERVICE TEMPERATURE
Annealed	600 - 800 N/mm2	87 - 116 ksi	-200 to +1100oC	-330 to +2010oF
			(for lightly stressed applications)
Spring Temper	800 - 1100 N/mm2	116 - 159 ksi	-200 to +1100oC	-330 to +2010oF
			(for lightly stressed applications)