Conversion Performance of Mixed Rust Converter Based on Phosphoric and Tannic Acids

The conversion performance of mixed rust converter based on phosphoric and tannic acids was analyzed by means of immersion test,electrochemical impedance spectroscopy and electron microscopy. The results show that the quality of phosphoricacid,tannic acid and their proportion affect the performance of rust converter. In the immersion test,when tannic acid content was 0.5%-1%,penetrant content was 3%-7%,and mass ratio of penetrant and phosphoric was 0.4-0.6,the conversion performance was relatively good. The ectrochemical impedance spectroscopy and electron microscopy tests show that after different converter treatments,the phosphating film densification and internal rust phosphating degree were different. Increasing the penetrant and inhibitor amount can improve the phosphating film compactness and internal rust phosphating degree.