Influence of Ni²⁺ on Chemical Coloring of Stainless Steel

The influence of concentration variation of nickel ions on chemical coloring of stainless steel was investigated.With the scanning electron microscopy (SEM) and the homemade mirror reflection device,the components and intensity of colored film were analyzed and characterized respectively.With the increasing of Ni2+ concentration in coloring liquid,the coloring initial potential descended,the coloring rate decreased and the coloring time was prolonged,the colored films glossiness was debased and the tone darkened.In colored films components,the Fe concentration showed downtrend vibrantly slightly,the O and Ni concentration did not change basically,the Cr concentration ascended slowly.When Ni2+ concentration was bigger than 8.0 g/L,the colored film got dim and the coloring liquid did not adapt to coloring any more.