How to Prevent Galvanic Corrosion Between Galvanized Steel and Stainless Steel?

Introduction

If you’ve ever mixed metals in a project—like using galvanized steel next to stainless steel—and noticed rust or damage over time, you’ve probably run into something called galvanic corrosion.

Don’t worry, you don’t need a science degree to deal with it. In this blog, we’ll explain what galvanic corrosion is in plain, everyday language, why it happens, and—most importantly—how to stop it before it starts.

We’ll also talk about how this affects things like stainless i beam, stainless steel round tubing, and stainless steel round tube—all of which are common in home, construction, and industrial use.

First Things First: What Is Galvanic Corrosion?

Let’s say you build a metal fence. You use galvanized steel posts and attach stainless steel parts to them. A few months later, you see rust forming around the joints. But wait—galvanized steel is protected, and stainless steel doesn’t rust easily. So what’s going on?

This is galvanic corrosion, and here’s a super simple way to understand it:

Think of metal like food. Some kinds spoil faster when they’re next to other foods. Just like how bananas ripen other fruits, some metals “trigger” corrosion in others—especially when they touch and get wet.

So when galvanized steel and stainless steel are connected and there’s water (like rain or humidity), a chemical reaction starts. One metal becomes the “giver” and starts to corrode, while the other one stays fine.

In this case, the galvanized steel usually takes the hit and starts corroding.

Why Does It Happen?

To keep it simple, here are the three things that make galvanic corrosion possible:

1. Two different types of metal (like galvanized steel and stainless steel)
   
   
2. Contact between them (they’re touching or connected)
   
   
3. Moisture or an electrolyte (like rainwater, humidity, or salty air)
   
   

Remove just one of those, and the corrosion stops.

Why You Should Care

Galvanic corrosion doesn’t just look bad—it can also:

• Weaken joints
  
  
• Damage expensive parts
  
  
• Shorten the life of a structure or machine
  
  
• Lead to costly repairs
  
  

If you’re working with items like stainless i beam or stainless steel round tubing, which are often used in construction or outdoor projects, you want them to last as long as possible without needing extra work or replacements.

So How Can You Prevent It?

Luckily, there are several easy and affordable ways to stop galvanic corrosion before it starts.

Let’s break them down in a way that makes sense.

1. Keep the Metals Apart

This is the easiest and most effective way. If the different metals don’t touch, they can’t react.

Use plastic, rubber, or nylon washers, gaskets, or spacers between the galvanized and stainless parts. That way, they’re not in direct contact.

Example: If you’re mounting a stainless steel round tube onto a galvanized bracket, insert a plastic washer in between. Problem solved.

2. Use Paint or Coating

Another method is to cover one or both of the metals so they’re not exposed to air or moisture.

• You can paint the surface of the galvanized steel.
  
  
• Or use a special anti-corrosion spray or sealant.
  
  
• Even clear nail polish (in a pinch!) can act as a temporary barrier.
  
  

If you’re working with a visible item like a polished stainless steel round tubing, this also keeps it looking clean and shiny.

3. Choose Compatible Fasteners

Sometimes, the corrosion starts at the bolts, screws, or nails. So, choose fasteners made from the same metal as the part you’re attaching to.

Example: If you’re working with a stainless i beam, use stainless fasteners—not galvanized ones. This helps reduce the chemical mismatch.

4. Dry It Out

Galvanic corrosion needs moisture. So keep the area dry if possible.

• Cover the joint from rain or splashes.
  
  
• Improve drainage.
  
  
• Add vents to let air flow and dry things out faster.

This is especially helpful in outdoor structures or in humid environments like coastal areas.

5. Use Galvanic Corrosion Tape or Gel

Yes, this is a real thing. You can buy special tape or anti-corrosion paste that blocks the reaction. It’s often used in electrical and marine work, but it works just as well in everyday projects.

6. Design Smart From the Start

If you’re building something new, plan for corrosion protection early.

• Put stainless parts higher than galvanized parts so rainwater doesn’t drip from stainless to galvanized.
  
  
• Keep water from pooling where the metals meet.
  
  
• Don’t use large stainless parts with small galvanized ones—this increases corrosion risk.
  

For instance, when installing stainless steel round tube rails on a galvanized steel base, consider sloping the design so water drains off easily.

 

Real-Life Examples

Let’s look at a few everyday situations where galvanic corrosion pops up—and how to fix them.

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Example 1: Deck Railing

You’re adding a deck railing made from stainless steel round tubing, and you use galvanized screws because they’re cheap and easy to find.

A few months later, you see rust around the screws. The solution? Replace the screws with stainless ones or put a plastic washer between the tubing and the fastener.

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Example 2: Warehouse Racks

You install storage racks using stainless i beam and galvanized shelf supports. If the building is in a humid place, corrosion can form where the pieces meet.

Prevent it by spraying the contact points with a protective coating, or placing rubber spacers in between.

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Example 3: Garden Trellis

You build a trellis using stainless steel round tube on galvanized metal feet stuck into the ground. Ground moisture + different metals = corrosion at the base.

A quick fix? Coat the base with waterproof paint or wrap it with anti-corrosion tape.

What If Corrosion Has Already Started?

Don’t panic. If you already see signs of corrosion, you can still take action:

1. Clean the area with a mild scrub or wire brush.
   
   
2. Dry it completely.
   
   
3. Apply a protective coating to stop it from spreading.
   
   
4. Separate the metals with a spacer or coating if possible.
   
   

In worst-case scenarios, replace the damaged part and redesign it with prevention in mind next time.

Special Note on Stainless Steel Shapes

When using metal shapes like:

• Stainless i beam
  
  
• Stainless steel round tubing
  
  
• Stainless steel round tube
  
  

…you want them to last for years, especially if they’re used in structures, equipment, or furniture. Galvanic corrosion can shorten their lifespan even though they’re strong metals. That’s why taking the right steps during installation makes all the difference.

Other Handy Tips

• Avoid salty environments if possible—saltwater speeds up corrosion.
  
  
• Inspect joints regularly for early signs of rust or corrosion.
  
  
• Keep stainless surfaces polished to make water slide off easier.
  
  
• Use quality parts from trusted suppliers.
  
  
  
  
  

Final Thoughts

Galvanic corrosion might sound technical, but stopping it is actually simple. If you remember just a few things, you’re ahead of the game:

• Don’t let different metals touch.
  
  
• Keep moisture away.
  
  
• Use protective coatings.
  
  
• Choose your fasteners wisely.
  
  

Whether you’re installing stainless steel round tubing for a home project or working with a stainless i beam for something bigger, preventing galvanic corrosion means fewer headaches and longer-lasting results.

With a bit of planning and the right materials, you can keep your stainless and galvanized metals working together—without one destroying the other.