About this Abstract |
Meeting |
MS&T21: Materials Science & Technology
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Symposium
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Advanced Materials for Harsh Environments
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Presentation Title |
Finite Element Corrosion Model and Experimental Characterization of Austenitic Stainless-Steel Engine Valves Oxidized in CO2 at 700 °C |
Author(s) |
Iman Abdallah, Louis Bailly-Salins, Xueyang Wu, Robert S Ullberg, Taeho Kim, Mohamed ElBakhshwan, Mark Carroll, John H Perepezko, Wen Jiang, Simon R Phillpot, Michael Tonks, Adrien Couet |
On-Site Speaker (Planned) |
Iman Abdallah |
Abstract Scope |
Current stainless-steel (SS) alloys used in engine cylinder exhaust valves are operated in harsh environment such as carbon dioxide, water vapor and gasoline. To reduce carbon gas emission, engines are being downsized and tend to operate at elevated temperatures (700 °C - 800 °C) for better performance and efficiency. At higher temperatures, SS used in the exhaust valves will undergo material degradation, corrosion and failure. In this work, corrosion modeling and experiments of high manganese SS alloys used in engine valves are being carried out to predict materials lifetime. Corrosion tests in pure CO2 and CO2+ 50% water vapor at temperatures of 700 °C were performed followed up to 1000 hours. Multiscale characterizations of the oxide layers are performed at selected times, using Glow Discharge Optical Emission and X-ray Photoelectron Spectroscopy, Scanning and Transmission Electron Microscopy. Corrosion kinetics is modeled in MOOSE using 3D geometry of valves. |