锌铝粉含量对无铬锌铝涂层性能的影响

Impact of Zinc-aluminum Powder Content on Performance of Chrome-free Zinc-aluminum Coatings

本文研究了锌铝粉含量对锌铝涂层的防腐蚀性、外观以及附着力等性能的影响。结果表明,锌铝粉含量在23%~32%范围内得到的无铬锌铝涂层表面致密完整,无裂纹、起泡等不良现象,片状锌铝粉层层堆叠、紧密结合,能够对金属基体起到有效的物理屏障防护作用;随着锌铝粉含量的增加,锌铝金属涂层自腐蚀电流密度先减小后增大,涂层自腐蚀电压以及涂层电阻先增大后减小,锌铝粉含量为29%时涂层自腐蚀电流密度最低(8.356×10^(-6)A/cm^(2)),活化后涂层电阻最大(620.6Ω·cm^(2)),耐蚀性最好。

The influence of zinc-aluminium powder content on the corrosion resistance,appearance and adhesion of zinc-aluminium coatings was studied in this paper.The results showed that the chrome-free zinc-aluminium coating with 23%~32%zinc-aluminium powder was compact and complete without cracks and foaming.The sheet-like zinc-aluminium powder were stacked layer by layer and bonded tightly,which could effectively protect the metal by physical shielding effect.With the increase of zinc-aluminum powder content,the self-corrosion current density of zinc aluminum metal coating decreased first and then increased,and the self-corrosion potential and coating resistance increased first and then decreased.The coating with 29%zinc-aluminium powder content had the lowest self corrosion current density of 8.356×10^(-6)A/cm^(2),and the highest resistance of 620.6Ω·cm^(2) after being activated,showing the best corrosion resistance.