Effect of composite magnetic microspheres and curing time on the corrosion and wear properties of phosphate ceramic coatings

Abstract

In order to enhance the corrosion and wear resistance of ceramic coatings in marine environment, different types of micro-nano structures were constructed on the surface of phosphate ceramic coatings by magnetic polystyrene (PS@Fe₃O₄) microspheres and curing time. Subsequently, the surface properties of the magnetic composite microspheres and coatings were characterized, and the corrosion and wear properties of the coatings were investigated. The results revealed that the microspheres were gradually decomposed with the increase of curing time, and the surface of the coating presented different micro-nano structure with convex, flat and concave. Compared to unstructured coating (NSC), the convex micro-nano structured coating (CXMNC) and concave micro-nano structured coating (CEMNC) possessed outstanding superhydrophobicity. Through three tests of the knife scraping, tape peeling and sandpaper abrasion, the coatings showed excellent bonding strength and mechanical durability. After a long immersion period (256 h), the impedance modulus of CXMNC and CEMNC were 27 and 15 times that of NSC, respectively. Compared with the NSC, the wear rate of CXMNC and CEMNC was reduced by 31.09% and 5.42%, respectively. Compared with the uncorroded samples, the wear rate of NSC, CXMNC and CEMNC after the immersion corrosion (30 days) was increased by 127.23%, 59.18% and 65.48%, respectively. Therefore, the micro-nano structured coatings have superior corrosion resistance and wear resistance to NSC, and CXMNC so as to CEMNC, which will provide better insight into the development of new corrosion-wear resistant materials.