Event Date
Corrosion of gas turbine components at high temperatures under salt deposits is a critical issue that adversely affects their performance and longevity. The analysis of failed components has indicated the presence of calcium-containing compounds in these deposits. These compounds may have different origins, e.g., sand particles, salts from marine atmospheres, atmospheric pollutants, etc. The consequences of the reactions between the salt deposits and the alloy substrate can result in enhanced solute depletion, and removal/ destruction of the external protective oxide scale. In this presentation, the focus will be on the effect of chromium concentration, and process variables such as temperature, time and atmosphere, on the deposit-induced corrosion of model binary nickel-chromium alloys. These alloys were exposed to films of calcium oxide and calcium sulfate individually as well as in combination with sodium chloride and sea salt. Characterization of the surface and cross-section of the post-corroded samples provided insights into the effects of alloy chemistry and process variables. Likely mechanisms for the corrosion process were developed. The current status of the research will be present.
