In order to clarify the formation mechanism and conditions for akaganeite in long-term exposure, the influence of the former corrosion results on akaganeite formation was investigated by simulated experi- ments in lab...In order to clarify the formation mechanism and conditions for akaganeite in long-term exposure, the influence of the former corrosion results on akaganeite formation was investigated by simulated experi- ments in laboratory. The combination of XRD, FTIR, SEM and EPMA enabled the identification of the rust layer formed on the surface. Accordingly, the nature of the rust layer and the amount of the corrosive species in the rust layer varied with the extension of the exposure. Among them, comparing with the corrosion condition in initial stage, the structure of rust layer after repeated wet-dry cycles was disad- vantage for akaganeite formation. Element CI aggregated at the interface between rust and substrate in the thick part can participate in the formation of akaganeite after the rust layer covered removed. The accumulation effect of salt deposited contributed to akaganeite formation under the condition that salt deposition rate was relatively low.展开更多
An eco-friendly rust converter treatment based on tannic acid was optimized by orthogonal experiment, and the adhesion of the epoxy top-coating system was evaluated. The results showed that the adhesion between the ep...An eco-friendly rust converter treatment based on tannic acid was optimized by orthogonal experiment, and the adhesion of the epoxy top-coating system was evaluated. The results showed that the adhesion between the epoxy coating and the rusted steel after treatment was enhanced from 1.93 to 5.97 MPa. This adhesion improvement was attributed to the formation of the micro-cracked tannic conversion layer and the increase of the compactness of the rust layer. The failure analysis suggested that the remainder rust was still the key issue for the further adhesion improvement of the coating system.展开更多
基金financially supported by the National Natural Science Foundation of China under the contract Nos.51301182 and 51671198the National Basic Research Program of China and Ministry of Science and Technology China under the contract No.2014CB643303
文摘In order to clarify the formation mechanism and conditions for akaganeite in long-term exposure, the influence of the former corrosion results on akaganeite formation was investigated by simulated experi- ments in laboratory. The combination of XRD, FTIR, SEM and EPMA enabled the identification of the rust layer formed on the surface. Accordingly, the nature of the rust layer and the amount of the corrosive species in the rust layer varied with the extension of the exposure. Among them, comparing with the corrosion condition in initial stage, the structure of rust layer after repeated wet-dry cycles was disad- vantage for akaganeite formation. Element CI aggregated at the interface between rust and substrate in the thick part can participate in the formation of akaganeite after the rust layer covered removed. The accumulation effect of salt deposited contributed to akaganeite formation under the condition that salt deposition rate was relatively low.
基金financially supported by the National Natural Science Foundation of China (Nos. 51001108 and 51131007)the National Basic Research Program of China (No. 2010CB934604)
文摘An eco-friendly rust converter treatment based on tannic acid was optimized by orthogonal experiment, and the adhesion of the epoxy top-coating system was evaluated. The results showed that the adhesion between the epoxy coating and the rusted steel after treatment was enhanced from 1.93 to 5.97 MPa. This adhesion improvement was attributed to the formation of the micro-cracked tannic conversion layer and the increase of the compactness of the rust layer. The failure analysis suggested that the remainder rust was still the key issue for the further adhesion improvement of the coating system.
