Incoloy®Alloy 20(UNS N08020) is an austenitic nickel-iron-chromium alloy with additions of copper and molybdenum. The nickel content makes Alloy 20 resistant to chloride-ion stress-corrosion cracking. Copper and molybdenum give resistance to reducing environments. The molybdenum content also provides good resistance to pitting and crevice corrosion. The chromium gives resistance to oxidizing environments such as nitric acid. The addition of niobium reduces the effect of carbide precipitation during welding, thus increasing the alloy’s resistance to intergranular corrosion.
Alloy 20 has exceptional corrosion resistance in sulfuric acid environments, and is used in a range of applications involving this acid. Other uses include the production of gasoline, solvents, explosives, inorganic and organic chemicals, pharmaceuticals, food and synthetic materials. For these and other applications, Alloy 20 is readily fabricated to produce mixing tanks, heat exchangers, process piping, pickling equipment, pumps, valves, fasteners and fittings.
Hot forming should be in the range 1400-2150°F (760- 1175°C). Incoloy® alloy 20 is normally used in the annealed condition. Annealing: 1800-1850°F (982- 1010°C)/ for a time commensurate with section size/AC.
Incoloy® alloy 20 is designated as UNS N08020. Standard product forms include pipe, tube, sheet, strip, plate, round bar, flat bar, forging stock, hexagon and wire. Rod, Bar, Wire and Forging Stock.
Plate, Sheet and Strip – ASTM A 240, ASTM A 480, ASTM B 463, ASTM B 906, ASME SA 240, ASME SA 480, ASME SB 463, ASME SB 906, ISO 6208, DIN 17750
Pipe and Tube – ASTM B 729, ASTM B 829, ASTM B 468, ASTM B 751, ASTM B 464, ASTM B 775, ASTM B 474, ASME SB 729, ASME SB 829, ASME SB 468, ASME SB 751, ASME SB 464, ASME SB 775, ASME SB 474, ISO 6207, DIN 77751
Other – DIN 17744, ASTM B 366, ASTM B 462, ASTM B 471, ASTM B 475, ASME SB 366, ASME SB-462, ASME SB 471, ASME SB 475