ALLOY 800 800AT 800H

ALLOY 800/800AT/800H TECHNICAL DATA

Type Analysis

Incoloy Incoloy 800 Incoloy 800H
Element Min Max Min Max
Nickel + Cobalt 30.0 35.0 30.0 35.0
Cobalt 2.00 2.00
Chromium 19.0 23.0 19.0 23.0
Copper 0.75 0.75
Iron Bal Bal
Silicon 1.00 1.00
Manganese 1.50 1.50
Carbon 0.10 0.05 0.10
Aluminum 0.15 0.60 0.15 0.60
Titanium 0.15 0.60 0.15 0.60
Sulfur 0.015 0.015

Description

Alloy 800 is an iron-nickel-chromium alloy with moderate strength and good resistance to oxidation and carburization at elevated temperatures. It is particularly useful for high-temperature equipment in the petrochemical industry because the alloy doesn’t form the embrittling sigma phase after long time exposure at 1200°F (649°C). Excellent resistance to chloride stress-corrosion cracking is another important feature of alloy 800.
Alloy 800H is a solution heat treated (2100°F/1150°C), controlled-carbon version of alloy 800 with improved elevated temperature properties. It has improved creep and stress-rupture characteristics in the 1100°F (593°C) to 1800°F (982°C) temperature range.

Applications

Typical applications for alloy 800 and 800H are – Heat exchangers and process piping; carburizing fixtures and retorts; furnace components; electric range heating-element sheathing; extruded tubing for ethylene and steam methane reforming furnaces; ammonia effluent coolers.

Physical Properties

Physical Properties °F British Units °C Metric Units
Density Room 0.287 lb./in.(3) Room 7.95 g/cm(3)
Electrical
Resistivity
70
200
400
600
800
38.9 microhm-in.
40.6 microhm-in.
43.0 microhm-in.
44.7 microhm-in.
46.1 microhm-in.
21
93
204
316
427
0.989 microhm-m
1.03 microhm-m
1.09 microhm-m
1.13 microhm-m
1.17 microhm-m
Mean Coefficient
of Thermal
Expansion
70-200
70-400
70-600
70-800
7.9 microin./in.-°F
8.8 microin./in.-°F
9.0 microin./in.-°F
9.2 microin./in.-°F
21-93
21-204
21-316
21-427
14.2 X 10(-6)m/m-K
15.8 X 10(-6)m/m-K
16.2 X 10(-6)m/m-K
16.6 X 10(-6)m/m-K
Thermal
Conductivity
70
200
400
600
800
80 Btu-in/ft²-hr-°F
89 Btu-in/ft²-hr-°F
103 Btu-in/ft²-hr-°F
115 Btu-in/ft²-hr-°F
127 Btu-in/ft²-hr-°F
21
93
204
316
427
11.5 W/m-K
12.8 W/m-K
14.8 W/m-K
16.6 W/m-K
18.3 W/m-K
Dynamic Modulus
of Elasticity
Room 28.5 x 10(6) psi Room 196 GPa

These properties apply to both alloys

Mechanical Properties

Alloy Form Condition Ultimate
Tensile
Strength,
ksi (MPa)
Yield
Strength
at 0.2%
offset,
ksi (MPa)
Elongation
in 2″
or 4D, percent
800 Sheet, Plate Annealed 85 (586) 40 (276) 43
800 Sheet, Plate
Strip, Bar
Annealed 75 (520)* 30 (205)* 30*
800H Sheet, Plate SHT 80 (552) 35 (241) 47
800H Sheet, Plate
Strip, Bar
SHT 65 (450)* 25 (170)* 30*

* – minimum
SHT – Solution heat-treated