Hot dip galvanizing and electroplating, which is more corrosion resistant?

Many friends want to know, galvanization processing includes hot galvanization and electrogalvanization, which is better? What's the difference? In response to this question, galvanzing plant manufacturer, Anno, will give you a simple answer.

The zinc coating of electrogalvanizing is more pure, while the impurity of zinc coating is more, which makes the zinc coating of hot galvanizing process easy to produce microbattery action, and this kind of situation is not easy to appear in electrogalvanizing process. In this case, the corrosion of electrogalvanizing is better than that of hot galvanizing.

However, the zinc coating in hot galvanizing process consists of pure zinc layer and ferrozinc alloy layer. The electroplating process only has pure zinc layer. Because there are more ferrozn alloy layers, the thickness of zn layer in hot-dip galvanizing process is much thicker than that in electrogalvanizing process. This makes the corrosion resistance of hot-dip galvanizing better than that of electroplating.

In the case of strong acidity, the corrosion resistance of electroplating with pure zinc coating is not ideal. However, hot galvanizing with pure zinc layer and ferrozinc alloy layer has better corrosion resistance. Therefore, the corrosion resistance of hot-dip galvanizing is stronger than that of electroplating.

There are no pores in the zinc layer of hot galvanizing process, but there are more pores in the zinc layer of electrogalvanizing process. Pores are prone to store corrosive media and cause corrosion, thus forming small pits. In this way, the corrosion resistance of hot-dip galvanizing is higher than that of electroplating.

In conclusion, it can be concluded that the overall corrosion resistance of hot-dip galvanizing is higher than that of electroplating.