Haynes 188 (UNS R30188 / W.Nr. 2.4683) is a cobalt-nickel-chromium-tungsten alloy that com- bines excellent high-temperature strength with very good resistance to oxidizing environ- ments up to 1095℃ for prolonged exposures, and excellent resistance to sulfate deposit hot corrosion. It is readily fabricated and formed by conventional techniques, and has been used for cast component. Other attractive features include excellent resistance to molten chloride salts, and good resistance to gaseous sulfidation.