Zinc Galvanizing Vs. Zinc Plating

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We hear a lot of buzz from advertisers about the wonders of owning this or that thing that has galvanized steel. But what exactly is galvanized and what makes it better than other types of steel. The truth is that some of these are just hype. The coating may be misrepresented to get you to buy the product. If you want to know more about the properties of galvanization versus plating read on.

The claim of galvanization is also made for products that are really only a zinc coating. This is done using a technological advancement known as high-speed galvanizing. The coatings are then sprayed with a polymer topcoat to add to its characteristics.

Although the process for zinc plating and zinc galvanizing are basically the same, there really is a big difference. The difference is the thickness of the zinc that is applied to the surface of the steel.

Zinc plating is generally applied using an electric current. This current is run through a zinc salt solution that has the pieces that are to be coated in it. The process leaves a coat of pure zinc on the item. The cheap hardware usually only gets about 15 microns and the more expensive products get more.

To get the best type of galvanized product you need to be certain that is has been hot dip galvanized. This adds a coating that is 50 microns thick, which means you get over 10x the protection with galvanization. This process dips a piece into molten zinc.

This process makes the item stronger and more resistant to corrosion. If you are buying an item that is going to be exposed to a lot of rain and other things that have a highly corrosive effect, this is the one you want. However because most people, everyday consumers, are not conversant of the differences in the processes, they buy the lesser items and find that they do not hold up as well.

Items with zinc coating are really not suited for use in the out-of-doors. If you purchase zinc plated hinges and bolts for things that will be exposed to the elements for any length of time you will see that you have to replace them over and over again. Although the items that are zinc-plated look great at the beginning, in about six months time you begin to see the change. The hot dipped hardware looks a bit duller but that is because of the thickness. In this case, dull means good and shinynot so much.

The next time you are in the market for a zinc coated part, remember the differences between zinc plating and zinc galvanizing.