溶胶凝胶旋涂法制备不锈钢Al_2O_3-CeO_2-Y_2O_3复合涂层

Al_2O_3-CeO_2-Y_2O_3 composite coating on stainless steel prepared by sol-gel spin coating method

本文以Al(NO3)3·9H2O,Ce(NO3)3·6H2——Y(NO3)3·6H2O为原料,PVP(聚乙烯吡咯烷酮)为稳定剂,用sol-gel法通过共沉淀水解再胶溶的办法,得到透明、稳定性能好的复合溶胶.利用旋涂法在SUS304不锈钢基体表面涂覆凝胶膜,经热处理得到复合涂层.采用XRD、SEM、EDS和电化学工作站等测试技术对复合涂层的相组成、微观形貌、成分及耐腐蚀性能等进行测试、表征.实验结果表明:用溶胶凝胶旋涂法能够成功制备出均匀的Al2O3-CeO2-Y2O3复合涂层.当主盐硝酸铝的浓度为0.60 mol/L,加入PVP含量为0.3 mol/L时,旋涂速度为3000r/min,旋涂8次,采用自然干燥再经过800℃煅烧能制得较为均匀连续,并且具有优良抗腐蚀性能的Al2O3-CeO2-Y2O3复合涂层.

A transparent and stable composite sol-solution was prepared using aluminum nitrate, cerium nitrate and yttrium nitrate as precursors, PVP as the stabilizer by means of sol-gel, coprecipitating hydrolysis and peptizing method. Spin coating method was used to coat the gel film on the substrate surface of the SUS304 stainless steel after heat treatment for composite coating. XRD, SEM, EDS and electrochemical testing technology were used to characterize the composite coating, phase composition, microstructure and electrochem- ical properties. The results show that A2O3-CeO2-Y2O3 composite coating can be successfully prepared by sol-gel spin coating method. The relatively eontinuous and homogeneous composite coating with good resistance to corrosion can be obtained under the condition that the concentration of aluminum nitrate is 0. 60 mol/L, the content of PVP addition is 0.3 mol/L , the spin speed is 3 000 r/min ,spin coating is 8 times, and calcined at 800 ℃ before natural drying.