UNS Number N08825
Other common names: Alloy 825, Inconel® 825
Incoloy 825 is a nickel-iron-chromium alloy with additions of molybdenum, copper and titanium. This nickel steel alloy’s chemical composition is designed to provide exceptional resistance to many corrosive environments. It is similar to alloy 800 but has improved resistance to aqueous corrosion. It has excellent resistance to both reducing and oxidizing acids, to stress-corrosion cracking, and to localized attack such as pitting and crevice corrosion. Alloy 825 is especially resistant to sulfuric and phosphoric acids. This nickel steel alloy is used for chemical processing, pollution-control equipment, oil and gas well piping, nuclear fuel reprocessing, acid production, and pickling equipment.
Alloy 825 (UNS N08825) Chemical Composition, %
| Ni | Fe | Cr | Mb | Cu | Ti | C | Mn | S | Si | Al |
|---|---|---|---|---|---|---|---|---|---|---|
| 38.0-46.0 | 22.0 min | 19.5-23.5 | 2.5-3.5 | 1.5-3.0 | .6-1.2 | 0.05 max | 1.0 max | 0.03 max | 0.5 max | 0.2 ma |
General Mechanical Properties
| Tensile (ksi) | .2% Yield (ksi) |
|---|---|
| 85 | 30-35 |
Alloy 825 has good mechanical properties from cryogenic temperatures to moderately high temperatures. However, exposure to temperatures above 1000° F can result in microstructural changes that significantly lower ductility and impact strength. Alloy 825 should not be used at temperatures where creep-rupture properties are design factors.
ASTM Specifications
| Pipe Smls | Pipe Welded | Tube Smls | Tube Welded | Sheet/Plate | Bar | Forging | Fitting |
|---|---|---|---|---|---|---|---|
| B423 | B424 | B425 | B564 | B366, B564 |