Structural evolution of derived species on FeAl surface exposed to a N2 + SO2 atmosphere: Experimental and theoretical study

Characterizations were performed by scanning electron microscopy analysis with energy dispersive spectrometry and scanning probe microscope for structural evolution of derived species on FeAl surface exposed to a N2 + SO2 atmosphere at high temperature. First principle calculations were also employed in order to clarify the formation of new product on the surface and its mechanism. The results demonstrate that the tendency of the structure with oxygen atoms involve a stronger interaction and lower energy to be formed with the surface and consequently the possible production of oxide-species is more probable and multiple aggregates with different shapes can be generated for the temperatures of 625 and 700 °C, with no preferential crystal habit. Sample treated at 775 °C denotes the production of hexagonal crystals, which is externally characterized by polyhedrons growing in axial direction as fibbers with flat faces that match with the alumina.