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.
Excellent resistance to reducing and oxidizing acids
Good resistance to stress-corrosion cracking
Satisfactory resistance to localized attack like pitting and crevice corrosion
Very resistant to sulfuric and phosphoric acids
Good mechanical properties at both room and elevated temperatures up to approximately 1000°F
Permission for pressure-vessel use at wall temperatures up to 800°F
|38.0-46.0||22.0 min||19.5-23.5||2.5-3.5||1.5-3.0||0.6-1.2||0.05 max||1.0 max||0.03 max||0.5 max||0.2 max|
Alloy 825 has a high level of corrosion resistance. It resists general corrosion, pitting, crevice corrosion, intergranular corrosion, and stress-corrosion cracking in both reducing and oxidizing environments.
Oil and gas well piping
Nuclear fuel reprocessing
Components in Pickling equipment like heating coils, tanks, baskets and chains
|Tensile (ksi)||.2% Yield (ksi)|
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.