Can You Weld Zinc Plated Steel? Everything You Need to Know

There’s a reason why there are all sorts of metal out there.

Different kinds of metal for different applications.

Sometimes, you’ll need to combine two very different metals to make it far stronger than before. Like an upgrade!

And since you’re a welder, you need to know what exactly made these metals so unique from one another.

Because once you do, you’ll realize just how much they’ll improve your workmanship to fit the picture you have inside your head!

One example of a fantastic combo is zinc and steel!

But it does raise the question: Can you weld zinc plated steel? And if so, how?

What is Zinc-plated Steel?

Unfortunately, there are a ton of ways to reduce the quality of metal with how many elements there are in existence.

Moisture is one of them.

And moisture is steel’s number one enemy because that leads to rust.

So we prevent that by zinc plating your steel!

Also called electro-galvanizing, zinc-plated steel isn’t as simple as you slapping on a metal sheet of zinc over the steel and calling it a day.

Well, that’s pretty close, actually.

You do layer zinc over your steel to protect it from corrosion. To do this, however, you’ll be giving it a bath.

But instead of soap and bubbles, you’ll be dunking it in a nice blend of electrolyte and zinc solution!

Then you send out an electric current on that solution for the zinc to stick to your steel and, ta-dah!

You now have zinc-plated steel!

Difference Between Galvanized and Zinc-plated Steel

So there’s another way to fight off the rust using zinc, and that’s by galvanizing steel.

You might find that word familiar from other names of zinc-plating, and electro-galvanizing.

Now, what makes these two things different?

Well, their purpose is pretty much the same: to prevent rust (or oxidization).

But how they’re made is where it branches out.

While an electrolyte-zinc solution is needed to plate zinc, you’ll be needing a tub full of pure zinc molten at a high temperature for your steel to take a dip in.

Once you remove it, you now have galvanized steel!

Hence, why this is called hot-dip galvanizing, and zinc plating is electro-galvanizing!

However, because you’re using molten zinc to add that corrosion-resistant layer, this makes galvanized steel much more durable than zinc-plated steel.

But galvanized steel doesn’t have the pleasing shine that zinc plating has when it looks like you dunked it in cement.

It does make it easier for you to distinguish them, though, so that’s good!

Welding Zinc Plated Steel

Can You Weld It?

Now, it all boils down to this question: can you weld zinc-plated steel?

Short answer: yes.

Except there’s a “but” in the end because it’s not as simple as you’d hope it to be.

Because, right off the bat, we already have a problem.

You’re going to weld steel coated in a different metal alloy.

One issue we normally have with welding two different metals is the huge contrast between their melting points.

So, on one hand, we have steel and its high melting point of 1, 510 degrees Celsius (for stainless steel) and a slightly lower melting point when you’re handling carbon steel with its 1, 371 degrees Celsius.

Then, you have zinc, and it has an EXTREMELY low melting point of 420 degrees Celsius.

It probably reminds you a bit of welding aluminum, doesn’t it?

Aluminum has a low melting point, too, but with its own protective layer that you have to get through first before you could get in there for the pure aluminum.

So, just like aluminum, you have to get rid of the zinc from your steel first.

Just the area where you’re going to weld! 

Because if you get rid of the ENTIRE zinc alloy across your metal, then that just ruins the purpose of why you’re using zinc-plated steel in the first place!

Going back, you can get rid of the zinc by using acid (like in prepping aluminum) or you can grind away the zinc.

Be sure to have a respirator on, though! Or do this under a fume hood!

Zinc is one of those metals that exude toxic fumes when there’s too much heat or when you’re grinding its layer off, so it’s better to have on the proper PPE uniform before dealing with this alloy.

Not only that, but too hot, and you’re looking at a porous-ruined, spattered piece of sheet metal now because of its awful fumes.

That’s why turning to flux core or stick welding is the best route!

There won’t be any gas involved from your welding, which the zinc’s fumes won’t react to!

Just be sure to keep a close eye on your heat, though, because your zinc layer can still let out too many fumes and ruin your steel a lot if left unchecked.

Conclusion

So, you want your steel to be protected from any of that nasty rusting, right?

Well, zinc-plating is the (cheapest) way to get there!

But welding is where problems start to come up.

Hopefully, after reading this article, you’ll learn that welding zinc-plated steel is entirely possible!

Complicated, but possible!

That’s why be extra careful in handling zinc, and you won’t be risking your health just to do your job!

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