Nickel alloy 188 is a cobalt-base alloy with excellent high-temperature strength and good oxidation resistance to 2000°F (1093°C). The high chromium level coupled with small additions of lanthanum produces an extremely tenacious and protective scale. The alloy also has good sulfidation resistance and excellent metallurgical stability displayed by its ductility after prolonged exposure to elevated temperatures.
Applications of Udimet 188:
Nickel alloy Udimet 188 is used in various applications, including gas turbine engine combustor cans, spray bars, flame holders, and afterburner liners. It finds extensive use in aerospace, gas turbine engines, petrochemicals, and nuclear power industries, where high-temperature performance and corrosion resistance are critical.
Normal product forms: bars, wire, forgings, sheets, plates, strips, pipes and tubes.
Specifications/Standard: AMS 5608
Chemical Composition:
Cobalt (Co): Balance
Nickel (Ni): 20-24%
Chromium (Cr): 21-23%
Tungsten (W): 13-15%
Manganese (Mn): 1.25% max
Iron (Fe): 3% max
Silicon (Si): 0.2-0.5%
Lanthanum (La): 0.02-0.12%
Physical Constants and Thermal Properties
Density: 0.330 lb/in³, 9.14 g/cm³
Melting Range: 2375-2425 °F, 1300-1330 °C
Specific Heat: 0.097 at 70 °F, Bru/lb °F, 405 at 21 °C, J/kg °C
Permeability: 1.0007 at 200 oersted
Coefficient of Expansion: 6.6 70-200 °F, 10-6in/in•°F, 11.9 21 – 93°C, μm/m • °C
