摘要 |
FIELD: metallurgy. ^ SUBSTANCE: invention relates to electroplating and may be used for electrochemical colouring of anodised aluminium by variable-polarity current. Proposed method comprises aluminium degreasing in water solution of sodium hydroxide, clarifying it in water solution of nitric acid, two-step DC anodising in two electrolytes, and colouring by variable-polarity current in electrolytes that contain cations of Cu, Ni, Co, Ag, Au. Note here that water solution of sulfuric or oxalic acid is used as anodising electrolyte while water solution of sulfosalicylic acid is used as second anodising electrolyte. Note also that aluminium anodising is carried out for 10-20 min while in second electrolyte it is performed for 20 min. ^ EFFECT: interference colouring in visible colouring spectrum. ^ 3 cl, 1 dwg, 6 ex |