Microstructural study on oxidation of aluminized coating on inconel 625

The high-temperature oxidation behavior of aluminized Inconel 625 has been examined using scanning electron microscopy (SEM) and fine-probe spot and linescan energy dispersive spectroscopy (EDS) microanalysis techniques. The formation of adherent slowly growing metallic coatings is essential for protection against severe environments. The coated (aluminized) and uncoated samples were subsequently oxidized in air at 1000 and 1100 °C to examine the performance of the aluminized coating. The micro-structural changes that occurred in both coated and uncoated samples were examined. It was found that coated samples showed superior performance against high-temperature oxidation, as compared to the uncoated samples. The coated samples revealed uniform and adherent oxidized layer, as compared to the uncoated samples. The oxidation behavior and multilayered microstructural morphology observed in the coated samples can be attributed to the interdiffusion and variation in kinetics of oxidation.