Technical Data Sheet

Haynes 188 / Udimet alloy 188 is a cobalt based nickel-chromium-tungsten alloy with a small addition of lanthanum to give a very protective scale. Alloy 188 combines excellent high-temperature strength with good resistance to both oxidizing environments up to 2000°F and to sulfate deposit hot corrosion. Alloy 188 has good forming characteristics and is capable of being forged, hot worked or cold worked, although it does work-harden very rapidly so frequent intermediate annealing treatments are recommended for complex forming operations. Alloy 188 is supplied solution heat treated at 2150°F and rapid air or water quenched to attain optimum properties. A combination of good fabricability and weldability makes Alloy 188 suitable for a wide number of applications, particularly in gas turbine components such as combustors, flame holders, liners and transition ducts.