| SPA-H is an anti-atmospheric corrosion structure and weathering steel developed by Japan. And SPA-H steel is a perfect shipboard container's material for its excellent anti-atmospheric and anti-seawater corrosion attribute. The surface quality of SPA-H steel is strictly demanded, whereas rusty spots appear on the surface of SPA-H steel produced by the continuous casting and rolling process in domestic steelworks. In order to give a helpful guidance in practical production, it is essential to study the behavior and mechanism of the oxidation rust. Oxidation kinetics of SPA-H steel which produced by CSP(Compact Strip Production) process were studied under constant temperature of 360℃, 460℃, 560℃, 660℃, 760℃, 860℃, 960℃and 1060℃for 60 minutes. Oxide compositions, phase structure and morphologies of oxides formed under different conditions are investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Numerical simulation for the rolling force, stress filed, strain filed and temperature filed in the rolling process are investigated by using ANSYS/LS-DYNA software with explicit algorithm finite element method (FEM).Oxidation behaviors of SPA-H are studied at elevated temperature in the experiment. The weight-change/time curves of isothermal oxidation show that the isothermal oxidation kinetics of SPA-H steel sheet follows logarithm law at 360℃and 460℃, it follows linear law at 560℃, while it follows linear law in the initial stage of oxidation and changed to the parabolic law later when temperature is 660℃or higher temperature. XRD analysis results show that is formed in the temperature rage of 560～660℃. SEM analysis results show that the oxidation scale is thin, continuous and fine when temperature is lower than 560℃. But it is so porous, discrete and loose that it is easier to fracture and peel off under the force of thermal and growing stress when temperature is higher than 660℃. All results prove that SPA-H steel has good oxidation resistance at 560℃and it has already lost anti-oxidant performance at 660℃. FeOThe variation of rolling force with time is studied in finishing roll process. The results reveal that the deeper depressive scalar, the larger rolling force to sheet as well as the largest rolling force.The variation of stress field and strain field with time are studied in finishing roll process. Stress field of one side and one center point in single reduction rolling process and the same sub-step in different reduction rolling process were analyzed individually. The results show that the sheet side Mises stress is larger than sheet centric Mises stress and the largest stress appeared in the deformed zone and the latter reduction rolling process is larger than the former ones. Strain field in single reduction rolling process and in different reduction rolling process were analyzed individually. The results show that the total Mises strain of undeformed sheet is the smallest in single reduction rolling process and keep largest after the sheet came from roll gap and the latter reduction rolling process is larger than the former ones.The variation of temperature field with time is studied in hot roll process. The results reveal that the temperature field of strip steel is intensively influenced by high pressure water descaling sprays. The temperature evidently drops on the heads of side and the surface of strip steel but keep constantly in the centre on the whole, temperature gradient is very large between the outside and the inside and will get smaller and smaller because of its interior heat conduction after high pressure water descaling sprays, finally the temperature was nearly uniform except for two heads.
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