1993 年 42 巻 479 号 p. 941-947
A new hot dip process for Zn-5%Al alloy coating on the steel structures was developed under suitable galvanizing conditions. The characteristics of the Zn-5%Al alloy coating were examined and its corrosion resistance was evaluated by a salt water spray test, an atmospheric exposure test and a coulostatic method.
It was clarified that from the results of chemical analysis, X-ray spectra, EPMA and hardness test, the coating prepared under the new type hot dip coating process exhibited superior qualities, especially, a coating layer consisting of Fe2Al5+Zn alloy formed in Zn-5%Al bath has the best corrosion resistance.
In addition, the results relating to the corrosion resistance clearly suggested that the coulostatic method may be useful for estimation of the rapid corrosion rate instead of the salt water spray test.