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The microstructure and oxidation behavior of Fe–B alloys have been investigated. Oxide scale cross-sectional microstructures oxidized at 1073 K for 100 h have been studied. EPMA investigations show that B 2 O 3 –SiO 2 oxides accumulates in the inner oxide layer which improves the oxidation behavior and oxide layer adhesion considerably. Cyclic oxidation kinetics data indicates that Fe–B 3.08 wt.% alloy presents the best oxidation resistance. The formation of diffusion zone in the Fe–B alloys indicate that the oxidation of the Fe 2 B boride is controlled by boron diffusion. The diffusion zone increases with time and reaches a maximum width of 60–65 μm. [ABSTRACT FROM AUTHOR]

The corrosion-wear behavior of Fe-3.5 wt.%B steel in liquid zinc was investigated via the block-against-ring technique. Owing to the protective ability of the Fe 2 B phase, this steel exhibited better corrosion-wear resistance than a 316L stainless steel. SEM, XRD, and EDS of the corrosion-wear interface indicated that the corrosion-wear process of Fe-3.5 wt.%B steel consists of the following steps: corrosion of the matrix, fragmentation and removal of FeZn 13 , and failure of the Fe 2 B. The intensified mechanical effect of wear resulted in significant deterioration (via fracture and removal of FeZn 13 , and spallation Fe 2 B) of corrosion-wear interface, which exacerbated corrosion, and facilitated the corrosion-wear process. [ABSTRACT FROM AUTHOR]

Highlights: [•] The as-received microstructure of bulk Fe2B comprises iron and silicon borides. [•] The orientation of Fe2B in liquid zinc strongly affects on corrosion resistance. [•] The Fe2B/FeB phase transition process of bulk Fe2B in liquid zinc occurs. [•] Phase transition and spalling dominate corrosion of Fe2B in liquid zinc. [Copyright &y& Elsevier]

Abstract: The interfacial morphology and corrosion resistance of low carbon Fe–B cast steels in zinc bath at 520°C were investigated. The results show Fe–B cast steel containing high Cr and Ni exhibits the best corrosion resistance to liquid zinc. The corrosion layers are composed of Γ-Fe3Zn10, δ-FeZn10, ξ-FeZn13 and η-Zn. The corrosion behaviour of Fe–B cast steels includes the following processes: the preferential leach and dissolution of Cr and Ni, the formation of Fe–Zn compounds controlled by zinc atom diffusion, and the spalling of borides without the supporting role of α-(Fe,Cr) matrix corroded by liquid zinc. [Copyright &y& Elsevier]

The interfacial morphologies and erosion-corrosion behavior of directional Fe-3.5 wt.% B steel in flowing liquid Zn-0.30 wt.% Al were investigated. Adding 0.30 wt.% Al to liquid zinc significantly improved the erosion-corrosion resistance of directional Fe-3.5 wt.% B steel, which possesses greater erosion-corrosion resistance when the [002] orientation of Fe 2 B is perpendicular to the erosion-corrosion interface. The erosion-corrosion interface consisted of an inhibition layer, determined by 0.30 wt.% Al, liquid zinc temperature and Fe 2 B orientation. This interface inhibited the diffusion, controlled Fe 2 B failure mode, resisted micromechanical scouring, and suppressed erosion-corrosion. Deterioration of the inhibition layer at the erosion-corrosion interface resulted in severe erosion-corrosion damage. [ABSTRACT FROM AUTHOR]

• Temperature effect on oxidation resistance of a Fe-Cr-B-Al-C-Mn-Si alloy is studied. • The oxidation resistance is best at 900 °C; it decreases with rising temperature. • The formation mechanism of oxide scale with bilayer/monolayer structure was discussed. • MnCr 2 O 4 oxides promote protective α-Al 2 O 3 oxide formation. • Selective oxidation of Al suppresses outward diffusion of Cr and Mn. The effect of temperature on the oxidation resistance of a novel wear-resistant Fe-10Cr-1.5B-6Al-0.3C-0.8Mn-0.6Si alloy is investigated. The mass growth rate shows that this alloy exhibits superior oxidation resistance at 900 °C. As the oxidation temperature increases from 900 °C to 1100 °C, the structure of the observed oxide scales transforms from a porous bilayer to a flat monolayer, while the oxidation rate increases sharply. The selective oxidation of Al suppresses the outward diffusion of Cr and Mn to form MnCr 2 O 4 oxides in the monolayer oxide scale, thereby decreasing the oxidation resistance at 1100 °C. [ABSTRACT FROM AUTHOR]