Structural characterisation of phosphated α-iron oxidised at 400 °C

α-Iron specimens were treated with phosphoric acid to obtain a conversion surface layer and the oxidation resistance of samples was studied at 400 °C in air. For oxidation time of 48 h, an important decrease in the oxidation kinetics was obtained in comparison with untreated α-Fe. The samples were characterised by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) analyses of the surfaces and these results are related to previous data on the oxidation of α-iron.