Corrosion behaviour of Fe–Al(–Ti) alloys in steam

The corrosion behaviour of binary Fe–Al alloys with Al contents ranging from 10 to 45 at.% Al and of ternary Fe–Al–Ti alloys with Al contents of about 25 at.% Al has been investigated in steam. No pre-oxidation has been applied. Saturated water vapour produced by a “steam generator” was passed over the samples in a quartz tube. The tests were conducted at 700 °C for 672 h without employing a carrier gas. The weight changes of the samples were determined after the experiments, and the formed scales were characterised by light optical microscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results for the different alloys vary quite markedly. Corrosion resistance for the binary alloys improves with increasing Al content, while the corrosion attack of the Fe–Al–Ti alloys is more severe.