熱浸鍍鋅防蝕原理與壽命

Anti-corrosion Mechanism and Service Life of Hot Dip Galvanizing

熱浸鍍鋅在防止鋼材腐蝕上已廣為人所用，但其會因環境的差異，造成抗蝕性的不同，進而影響其保護底材的壽命。本文乃就熱浸鍍鋅層的電化學特性和在大氣、水溶液、混凝土中的腐蝕行為和抗蝕原理做一介紹，進而就已有之數據說明不同環境下之壽命，其中以氯離子和硫酸根濃度影響最大，尤其前者，值得設計與使用者多加留意。

Hot dip galvanizing has been widely used to prevent steel from corrosion. However, its anti-corrosion ability changes with the environment resulting in the change of its service life. In this paper, electrochemical characteristics of different phases in the zinc coating layer and corrosion behaviour and anti-corrosion mechanism of hot dip galvanizing in atmosphere, aqueous solution and concrete are introduced. Furthermore, its service life in different environment is described by the published data which shows that the concentrations of chloride and sulfate ions possess the greatest influence on its service life, especially the former. These results are noticeable for designers and users to pay more attention.