High-temperature oxidation behaviour of Fe-Mn-AI-Si-C alloys in thermal cycling tests

Abstract

A study was made of the behaviour under thermal cycling in air of a series of Fe-Mn-AI-Si-C alloys which had shown good resistance to isothermal oxidation tests. Alumina based oxides are formed interspersed with spinels more or less rich in manganese. These spinels undergo microspalling during the cycling, with a continuous loss of materials contained, within acceptable values up to a temperature of 750°C. The role of silicon is particularly important in supporting the formation of the alumina film and in promoting the diffusion of manganese instead of iron in the formation of the spinels, which result in higher resistance to thermal shocks.