The influence of Methionine (MTI) on corrosion behavior of Twinning induced plastic (TWIP) steel in 3.5wt.% NaCl solutions was investigated using electrochemical techniques, scanning electron microscopy (SEM), white light interferometer (WLI) analyses and Raman spectra. With increasing inhibitor concentration, the corrosion inhibition rate first increased and then decreased, and the maximum inhibitor efficiency was found to be 30 mg l−1 MTI. MTI was acting as a mixed-type inhibitor. The inhibition effect of MTI could also be evaluated by SEM and WLI results, and the trend was the same as that obtained by electrochemistry. At the same time, Raman spectra results showed that MTI was adsorbed on the surface of the steel.

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The failure of brake performance, which is caused by thermal recession under the emergency brake, results in traffic accident frequently. Based on excellent wear-resisting properties of locust’s non-smooth surface structure, bionic brake disc with special surface micro-structure was designed. According to the thermal analysis theory, transient temperature field analysis of the bionic brake disc during the braking process under different initial velocity was analyzed. The results showed that bionic brake disc has excellent heat dissipation ability, which is beneficial to improve the brake performance. The non-smooth surface can store air and dissipate heat, thus reducing the thermal fatigue and thermal wear caused by temperature rise. This research provides a theoretical basis for designing bionic brake discs with excellent heat dissipation performance.

The uneven friction of brake disk leads to the brake failure, which frequently results in serious traffic accidents. Based on the excellent wear-resisting properties of locust’s non-smooth surface structure, bionic brake disc with special surface micro-structure was designed. Utilizing ANSYS Workbench, the braking time and the stress distribution of both the bionic model and the smooth model during the whole process of brake under different initial velocity were analyzed. Compared to the smooth model, results showed that the braking time and contact stress decrease in a certain extent, indicating brake disc with special surface micro-structure exhibits relatively excellent braking performance and wear resistance. The results provided theories for exploring an optimization the method used to design brake discs with excellent braking performance and wear resistance.

Based on explicit finite difference algorithm, finite element model of steel plate with transverse surface crack in rough rolling was found. The evolution regularity of transverse surface crack in rolling process was calculated with the model, and effect of different crack sizes, different friction coefficients and different roll diameters on crack evolution were studied. The research indicated that, in rolling direction, the crack tip stress changed from tensile stress to compression stress and then tensile stress again; length and depth of crack both had effect on the healing and propagation of the crack, and mostly in the way of influencing displacement of freedom surface of the crack; different friction coefficients showed no effect on crack tip propagation, but low friction coefficient would be in favor of crack healing at crack bottom; small roll diameter would lead to high crack tip tensile stress and more propagation at crack tip.