Protection of Phosphating and Sealing for Iron Cultural Relics

The treatments of sealing, phosphating, and sealing-phosphating were carried out on the surface of low-carbon steel. The protections of sealing, phosphating and sealing-phosphating for substrate were studied by immersion testing, salt-spray testing and electrochemical testing. The results show that phosphating, and sealing-phosphating had good protection for the low-carbon substrate compared with no-treatment and sealing in immersion test and salt-spraying test. The specimen treated by sealing combined with phosphating showed the best anticorrosion because sealing and phosphating could bring synergistic effect when they were used together, and showed better protective effect to the substrate.