论文部分内容阅读
采用恒流法,在铝酸盐系电解液中对5083铝合金进行微弧氧化处理。并利用扫描电镜和动电位极化曲线等手段,研究了不同电流密度下制备的陶瓷层的微观形貌及耐蚀性。结果表明:随电流密度的提高,更多的氧化物沉积在膜层表面,使之厚度增大。当电流密度为3.5 A·cm~(-2)时,陶瓷层的自腐蚀电位正移至-0.493 V,自腐蚀电流密度降至3.64×10~(-7)A·cm~(-2)。从而,微弧氧化陶瓷层显著提高了基体铝合金的表面耐蚀性。
Using constant current method, 5083 aluminum alloy was treated by micro-arc oxidation in aluminate electrolyte. The microstructures and corrosion resistance of ceramic layers prepared at different current densities were studied by scanning electron microscopy and potentiodynamic polarization curves. The results show that with the increase of the current density, more oxides are deposited on the surface of the film to increase its thickness. When the current density is 3.5 A · cm -2, the self-corrosion potential of the ceramic layer is shifted to -0.493 V and the self-corrosion current density is reduced to 3.64 × 10 -7 A · cm -2. . Thus, the micro-arc oxidation ceramic layer significantly improves the surface corrosion resistance of the matrix aluminum alloy.