Corrosion behavior of typical hot rolled sheets in humid storage environments

Purpose The purpose of this paper was to study the relationship between safe storage life and storage mode of hot-rolled sheet (Q235, X70) in humid environment, and a prediction model of safe storage life under different storage modes was established. Design/methodology/approach The corrosion behavior of hot-rolled sheets under different storage conditions was studied with immersion experiment and morphology observation. Findings The results show that pitting occurs on the hot-rolled sheets in humid environment, and the corrosion behavior is strongly related with the storage mode. When they are stored separately, the number and depth of pits first increase and then decrease as the Cl− concentration rises, while for the stack storage, pit depth increases with increasing Cl− concentration. The safe storage time of separate storage is longer than that of stack storage. Based on this, a model of chloride ion concentration and storage life was established. Originality/value A storage safe life model of hot-rolled sheet in humid environment is proposed.