热浸镀无铵助镀预处理对Zn-0.05%Al锌浴的影响

Effects of Hot Dip Ammonium-free Fluxing Pretreatment on Zn-0.05% Al Znic Bath

针对热浸镀锌工艺传统助镀处理造成的Zn-Al合金浴中Al失效和助镀烟尘污染问题,采用无铵助镀工艺对试样进行预处理,借助于称重法、ICP-AES、SEM、EDS等分析了无铵助镀下Zn-0.05%Al合金浴中Al含量随浸镀试样数量增加的变化趋势及无铵助镀对镀层组织结构、锌耗的影响,探讨了无铵助镀对Zn-0.05%Al合金浴中Al含量波动的影响。结果表明:与传统锌铵助镀相比,无铵助镀条件下锌浴中的铝含量与浸镀试样数量呈简单线性关系,无铵助镀对锌浴具有稳铝效果;无铵助镀条件下锌浴的无益锌耗降低,生成的锌渣量降低;无铵助镀对镀层的厚度和物相组成影响不明显,但镀层的致密性提高。

Aiming at the aluminum failure in Zn-Al alloy bath and dust pollution problem caused by traditional fluxing process in hot dip galvanizing, the test samples were pre-treated by ammonium flee fluxing process. The change trend of the aluminum content in Zn-0.05%Al alloy bath under ammonium-free fluxing with the increase of the number of hot dipped workpieces, and the influences of ammonium flee fluxing on the microstructure and zinc consumption of the coating in hot dipping were analyzed by mass testing method, ICP-AES（atomic emission spectrometer）, SEM （scanning electron microscope） and EDS （energy dispersive spectrometer）, meanwhile, the influences of ammonium flee fluxing process on the Al content fluctuation in Zn-0.05% Al bath were discussed. The results show that compared with the traditional fluxing,a simple linear relationship between aluminum content in Zn bath and the number of hot dipped workpieces is found in ammonium flec fluxing. The ammonium free fluxing has stabilizing effect for aluminum in zinc bath. The useless zinc consumption and zinc slag quantity reduce in hot dipping by ammonium rice fluxing process. The influence of ammonium free fluxing on the thickness and phase composition of the coating is not obvious, however, the density of the coating improves.