A New Alumina-Forming Ni-Co-Cr Base Alloy for Service in Gas Turbine Engine Combustors and Other High-Temperature Applications

HAYNES^® 233™ alloy based on Ni-Co-Cr-Mo-Al system has been developed for service at high-temperatures. The origins of 233 alloy can be traced to a couple of Haynes alloys: 230 and 214 alloys. The former is a premier high-temperature alloy with superb creep strength and widely accepted in the gas-turbine industry. It is also chromia-forming. The alumina-forming 214 alloy with its 4.5% Al content possesses outstanding oxidation resistance at high temperatures, but its creep strength above ~ 1800°F is very poor. The new 233 alloy attempts to bridge this performance: Achieve the oxidation resistance up to 2100°F possessed by 214 alloy along with creep strength approaching that of the 230 alloy. This paper will present preliminary results for 233 alloy from the products from the first production heat. We will present tensile and creep properties of the alloy in the range of 1700°F – 2100°F, and oxidation properties from static oxidation tests at 1800°F and 2100°F as well as dynamic oxidation tests at 1800°F. These results will be compared and discussed with those of popular gas-turbine alloys such as 230, 617, and X alloys. Microstructural characteristics of the alloy will be presented.