纳米SiO_2复合处理对7A52铝合金微弧氧化陶瓷层孔隙率及性能的影响

摘要

通过向电解液中添加纳米二氧化硅颗粒(n-SiO_2),经微弧氧化,在7A52铝合金表面制备n-SiO_2复合陶瓷层,研究n-SiO_2复合处理对陶瓷层孔隙率及性能的影响.结果表明,经n-SiO_2复合处理后,陶瓷层孔隙尺寸减小,孔隙率降低,致密性提高,因而陶瓷层显微硬度和抗盐雾腐蚀性能显著提高.n-SiO_2在放电通道处沉积是陶瓷层致密性提高的主要原因.%Ceramic coatings incorporated with SiO_2 nanoparticles were fabricated on 7A52 aluminum alloy during micro-arc oxidation by mixing SiO_2 nanoparticles into the electrolyte. The porosity and properties of the ceramic coatings were investigated. The results show that coatings embedded with SiO_2 nanoparticles exhibit lower porosity and improved compactness, which lead to higher microhardness and better corrosion resistance. The enhancement of compactness can be attributed to SiO_2 nanoparticles deposited in discharge pores during the micro-arc oxidation process.