烷基糖苷对硫酸盐无光镀锌的影响

Effect of alkyl glycoside on dull zinc plating from sulfate bath

采用烷基糖苷为主添加剂进行硫酸盐体系无光镀锌,表征了镀层的光泽度、结合力和耐中性盐雾腐蚀性能。基础镀液组成和工艺条件为:ZnSO_4·7H_2O 225g/L,Na_2SO_4 70g/L,Al_2(SO_4)_3 25g/L,温度(25±5)°C,电流密度2A/dm^2,时间25min(镀层厚度8~12μm)。对比研究了分别采用烷基糖苷和葡萄糖作添加剂时所得镀锌层的外观和微观形貌。结果表明,使用烷基糖苷作添加剂时所得锌镀层外观均一,结晶致密,具有良好的基体结合力和耐蚀性。

Dull zinc plating was conducted in a sulfate bath with alkyl glycoside as a main additive. The coating＇s glossiness, adhesion and resistance to neutral salt spray corrosion test were characterized. The basic bath composition and process conditions are as follows： ZnSO4·TH2O 225 g/L, Na2SO4 70 g/L, Al2（SO4）3 25 g/L, temperature （25±5）℃, current density 2 A/dm^2, and time 25 rain （with a coating thickness of 8-12 μm）. The appearance and microscopic morphology of zinc coatings prepared from the bath with alkyl glycoside or glucose as an additive were comparatively studied. The results showed that the zinc coating obtained from the bath with alkyl glycoside as an additive features uniform appearance, compact crystalline,strong adhesion to substrate and good corrosion resistance.