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Electron backscatter diffraction (EBSD) analysis has been presented to investigate the microstructure and microtexture evolutions of deformed oxide scale formed on a microalloyed steel during hot rolling and accelerated cooling. Magnetite and wustite in oxide layers share a strong {0 0 1} and a weak {1 1 0} fibres texture parallel to the oxide growth. Trigonal hematite develops the {0 0 0 1} basal fibre parallel to the crystallographic plane {1 1 1} in magnetite. Taylor factor estimates have been conducted to elucidate the microtexture evolution. The fine-grained magnetite seam adjacent to the substrate is governed by stress relief and ions vacancy diffusion mechanism. [ABSTRACT FROM AUTHOR]

Highlights: [•] The oxidation behaviour of the Nb–V–Ti microalloyed steel is investigated. [•] The coarse-grained steel substrate has detrimental effect on adhesion properties. [•] High magnetite content is attributed to grain-boundary oxidation above 570°C. [•] Grain refinement mechanism is proposed to generate the tight oxide scale. [ABSTRACT FROM AUTHOR]

The breakaway oxidation behaviour of ferritic stainless steels 430, 443 and 445 has been investigated at 1150 °C in humid air. The oxidation kinetics exhibited significant differences among the three ferritic stainless steels. A uniform and steady growing oxide scale was developed on the 430 steel with an even steel/oxide interface. Local breakdown of the initially protective oxide scale occurred and oxide nodules were developed on the 443 and 445 stainless steels, resulting in irregular and rough steel/oxide interfaces. The breakaway oxidation behaviour was significantly influenced by the microstructure and the composition of the oxide scale. The Mn-Cr spinel oxide formed on top of the Cr 2 O 3 scale in Mo alloying 445 steel can greatly minimise the Cr depletion. [ABSTRACT FROM AUTHOR]