The effect of chemical composition on selective oxidation of bake hardenable steel

Abstract

Purpose -The purpose of this paper is to study the effect of chemical composition on the selective oxidation on the surface of bake hardenable steel, and on the surface of modified bake hardenable steel with titanium addition, annealed at different dew points. Design/methodology/approach -The subject scope of the paper is the selective oxidation. The methodology used is the annealing of steels at different dew points, and the surface characterization by using atomic force microscopy, X-ray photo electronic spectroscopy, and glow discharge optical emission spectroscopy. Findings -The modified bake hardenable steel showed a higher oxidized area than the bake hardenable steel. The optimum condition for annealing of the bake hardenable steel was at 8008C with 2308C dp and 2 608C dp as selective oxidation is less voluminous. Research limitations/implications -One suggestion for future works is the use of transmission electron microscopy for the evaluation of selective oxidation on the steel surfaces. Practical implications -One practical implication is the determination of the optimum condition for annealing of the bake hardenable steel in the steel plant, decreasing the selective oxidation and increasing the quality of galvanized steels. Another implication is the discard by the steel industry of the development of the modified bake hardenable steel. Originality/value -The originality of the present work is to use advanced surface analysis techniques to quantify the selective oxidation on the surface of commercial steels. The selective oxidation on the surface of steels must be minimized in order to increase the wet ability of zinc layer on the steel surface.