Study of the thermo-mechanical and fracture behaviour of iron oxide scales at room temperature and at high temperature

Overview & Synopsis

During the hot rolling process, a thin layer of oxide scale forms on the surface of steel slabs, leading to surface defects. Descaling, by applying high-pressure water to the steel surface, helps limit the thickness of the oxide and improve surface quality. This study aims to enhance the understanding of the phenomena involved in secondary descaling. Several low-carbon steel grades, characterised by differences in descaling, have been selected to analyse their discrepancies in industrial configurations. The behaviour of the oxide scale is evaluated through in situ high-temperature X-ray diffraction, enabling control over oxidation. This analysis includes both phase and stress evaluations to observe transitions in the behaviour of the oxide, particularly the relaxation of internal stresses above 700°C. Mechanical properties of the oxide are determined through indentation tests conducted at both room temperature and elevated temperatures. At lower temperatures (