Effect of alloy composition on the sodium-sulfate induced hot corrosion attack of cast nickel-base superalloys at 900 CThe effects of Cr, Al, Ti, Mo, Ta, Nb, and W content on the hot corrosion of Ni-base alloys were examined experimentally. The superalloys were tested for 300 1-hr cycles at 900 C in a Mach 0.3 burner rig flame containing 0.5 ppmw sodium. The data reveal that the best corrosion resistance is obtained when the Cr content is greater than 12 percent; however, good resistance is detected in some alloys with Cr content less than 10 percent provided that the Al content is less than 2.5 wt pct and the Ti content is less than 4 wt pct. It is observed that the influence of W, Ta, Mo, and Nb content on resistance is dependent on Al and Ti contents. The derivation of an equation for estimating hot corrosion attack as a function of alloy composition using multiple linear regression analysis is described. The applicability of the equation is tested using various data sets of alloys. It is noted that the equation can be used to explain the effects of alloy composition on attack rates.
Document ID
19880022801
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Stearns, C. A. (NASA Lewis Research Center Cleveland, OH, United States)
Deadmore, D. L. (NASA Lewis Research Center Cleveland, OH, United States)
Barrett, C. A. (NASA Lewis Research Center Cleveland, OH, United States)
Date Acquired
August 13, 2013
Publication Date
January 1, 1987
Subject Category
Metallic Materials
Meeting Information
Meeting: Alternate alloying for environmental resistance