Is Galvanized Steel Magnetic?

Galvanizing is when you add a layer of protection to steel from rust and corrosion by coating it with zinc. This makes the material long-lasting and durable against nature.

This is perfect for man-made structures such as buildings, bridges, and even railway tracks. 

Is Galvanized Steel Magnetic?

Naturally, steel is a magnetic material. But a common question is, is galvanized steel magnetic?

In this article, we go into depth about the process of galvanizing steel and whether the steel remains magnetic after the galvanizing process. We also discuss whether stainless steel is magnetic!

What Is Galvanizing?

By applying a very thin layer of zinc to steel, the process of galvanizing renders it resistant to rust and corrosion.

In a vat of hot, molten zinc, we submerge clean steel as part of the hot-dip galvanizing procedure. It is a protective measure to prolong the life of steel. 

The thin zinc coating serves as a sacrificial cathode once it has been applied to the steel. Simply put, zinc releases electrons more frequently than iron.

So, when a corrosive agent attacks the galvanized steel, the corrosive agent is met with the zinc rather than the steel. 

Essentially, zinc protects the steel from the bad guys. 

Ironically, some chemical processes can strengthen zinc while destroying steel. One illustration of this is the zinc carbonate that develops on the surface of steel when it combines with atmospheric moisture and carbon dioxide.

However, zinc, in any form, is not magnetic. Does this affect the pull of the steel beneath it? Or is galvanized steel magnetic?

Does Galvanized Steel Have A Magnetic Pull?

Iron is naturally magnetic. Iron makes steel. Meaning steel has a magnetic pull. 

With the Earth’s core being made of molten iron, it only makes sense that steel has a strong magnetic pull that we use in our everyday lives.

Everyone is aware that steel used in domestic applications is magnetic. You can use refrigerator magnets to keep your notes and images because your refrigerator’s door is composed of steel.

So, does the use of zinc stop steel from being magnetic? The answer is no. Using molten zinc to galvanize steel does not stop the magnetic pull. 

Once the steel is galvanized, it will still have its natural magnetic properties that can be used in various ways across the world. 

Why Is Austenitic Stainless Steel Not Magnetic?

Now, it is important to note that not all steels are magnetic. There are some steels that naturally have no magnetic properties but can become magnetic once molded and formed into something else. 

The most known non-magnetic steel is austenitic stainless steel. Austenitic stainless steels have a different microstructure from other steels which makes them extremely malleable.

They are great for forming springs and more delicate products. 

To make them acid-resistant, they might be forged from a molybdenum and iron alloy. They are frequently found in kitchenware, cutlery, and cookware.

Nickel may also be added to austenitic stainless steels and this is what makes them non-magnetic. That quality can be very helpful. For example, you wouldn’t want the MRI machine in your hospital to be magnetic.

It is made of austenitic stainless steel because of this.

Many debates over whether galvanized austenitic stainless steel would be magnetic. But due to the underlying steel having no magnetic properties, galvanizing it would not make it magnetic. 

Magnetic Steels 

There are three main phases of steel. Each of these is determined by the allowed content and the thermal condition of the steel. The first one is what we just talked about, austenitic stainless steel.

The other two are:

Martensitic Stainless Steel 

Martensitic stainless steels are created from iron with 12–17% chromium and 0.1–1.2% carbon.

They may contain a small amount of nickel, which enables the addition of more chromium and increases the corrosion resistance of the steel. (Not as resistant to corrosion as galvanized steel, but still rather durable.)

Is Galvanized Steel Magnetic? (1)

Martensitic stainless steel has a microstructure that is common to cast iron. This can then be formed into items such as bowls and even surgical instruments.

This regular microstructure allows this steel to be magnetic. 

This type of stainless steel is often grouped into a grade of 410, 420, and 440. Identifying themselves as magnetic steels which is a compound of iron.

Ferritic Stainless Steel 

A type of stainless steel alloy called ferritic steel has a chromium content of over 12%. Two crucial characteristics set it apart from other types of stainless steel: its molecular grain structure and chemical makeup.

A straight chromium non-hardenable class of stainless alloys with chromium levels ranging from 10.5% to 30% and a carbon percentage of less than 0.20% is known as ferritic stainless steel.

Ferritic stainless steel is grouped into grades 439, 439, 44, and 446. 

Ferritic stainless steels differ from austenitic stainless steels in that they often contain little or no nickel.

Martensitic stainless steels, the majority of which also don’t contain nickel, also share this characteristic with them. Last but not least, ferritic steels are distinguished by their low carbon content.

Final Thoughts 

So, is galvanized steel magnetic? Yes, even after dipping steel into molten zinc, it will still have a magnetic pull. 

Galvanized steel is then used for various structures such as buildings, bridges, and even smaller items such as staircases, ladders, and walkways.

You can find galvanized steel all around us that is protected from corrosion and rust. 

All you have to do is look! 

Frequently Asked Questions 

What Type Of Steel Is Most Magnetic?

Martensitic stainless steel is the most magnetic material. It contains large quantities of ferrite in its microstructure which is made of iron and other elements. Making it highly magnetic. 

How Can You Tell If Steel Is Galvanized?

When a pattern on the metal known as a spangle pattern is present, you may tell that it has been galvanized. A spangle design resembles someone painting the metal with a sponge after dipping it in gray paint.

Luke Powell
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