Metal dusting resistant alumina forming coatings for syngas production

Metal dusting corrosion of NiCrAl(Y)-based alumina forming coatings has been simulated in carbon-supersaturated environments (CO-H₂) at 650 °C. Atmospheric plasma spray (APS) and powder plasma welding (PPW) methods have been employed to deposit alumina forming coatings on Inconel 601 substrate alloy surfaces. Since most currently available high temperature alloys are prone to metal dusting, understanding and thereby controlling metal dusting corrosion is key to many operations and developments related to syngas production. The focus of this research is to evaluate the performance of alumina forming coatings under laboratory conditions. In addition to the effect of coating chemistry and microstructure (based on method of application) on the corrosion process, the mechanistic aspects of metal dusting are discussed with particular attention to the stages of microstructure evolution as degradation proceeds.