热喷涂陶瓷涂层在NaCl溶液中的耐腐蚀性

Corrosion Resistance of Thermal Sprayed Ceramic Coatings in NaCl Solution

摘要: 采用超音速火焰喷涂与等离子喷涂制备了WC-Cr₃C₂-Ni涂层与Al₂O₃-40TiO₂涂层，研究了两种热喷涂陶瓷涂层在3.5wt% NaCl溶液中的耐腐蚀性。结果表明：WC-Cr₃C₂-Ni涂层在3.5wt% NaCl溶液中存在钝化现象，具有良好的耐点蚀能力。与Al₂O₃-40TiO₂涂层相比，WC-Cr₃C₂-Ni涂层的腐蚀电位更高且腐蚀电流密度更小，WC-Cr₃C₂-Ni涂层的电阻R_ct约为Al₂O₃-40TiO₂涂层的30倍，这表明：WC-Cr₃C₂-Ni涂层在3.5wt%NaCl溶液中的耐腐蚀性更好。

Abstract: WC-Cr₃C₂-Ni coating and Al₂O₃-40TiO₂ coating were prepared by high-velocity oxygen-fuel spraying and plasma spraying, respectively. The corrosion resistance of the two thermal sprayed ceramic coatings in 3.5wt%NaCl solution was studied.The results show that WC-Cr₃C₂-Ni coating has passivation phenomenon in 3.5wt%NaCl solution and has good pitting resistance. Compared with Al₂O₃-40TiO₂ coating, the corrosion potential of WC-Cr₃C₂-Ni coating is higher and the corrosion current density is lower.The resistance R_ct of WC-Cr₃C₂-Ni coating is about 30 times of Al₂O₃-40TiO₂ coating, which indicate that the corrosion resistance of WC-Cr₃C₂-Ni coating in 3.5wt%NaCl solution is much better than that of Al₂O₃-40TiO₂ coating.