Multilayered Coatings for High-Temperature Steam Oxidation: TGA Studies up to 1000 °C

The aim of the study was to obtain a preliminary data focused on the steam oxidation performance of multilayered coatings deposited on 310 stainless steel and 800H Incoloy. The coatings were obtained through the aluminizing thermal diffusion technology with the formation of aluminides; some coating options had an additional top layer of selected composition. In this study, five different coating systems, as well as uncoated metals, were exposed at 1000 °C using thermogravimetric analysis instrumentation simulating an initial stage of steam oxidation corrosion. In this work, along with determination of the mass change of the samples, microanalyses using light optical microscopy, scanning electron microscopy (SEM) equipped with energy x-ray dispersive spectrometry (EDS), as well as surface micro-hardness determination, have been carried out. The designed coating systems demonstrated promising high-temperature steam oxidation performance with no breakaway degradation issues.