Zirconia vs. Aluminum Oxide: Which to Choose


Zirconia vs. Aluminum Oxide is the two most common types of sandpaper, belts, and pads. This guide can help you choose the right one.

Here, we will look at these abrasives, their differences, and their intended uses.

Zirconium Oxide vs. Aluminum Oxide: Definition

Aluminum Oxide

Several Grades of Aluminum Oxide

Several Grades of Aluminum Oxide

Alumina material is the most commonly used abrasive in the world. You will most often see it is grits ranging from 24 to 600. In fact, it is added to most other abrasive products, including ceramic abrasives, to improve their cutting ability. 

Companies produce alumina by purifying bauxite. Manufacturers use a smelting process involving coke, iron borings, and temperatures that reach 2,000 degrees Fahrenheit. This process accounts for 90 percent of all the abrasive materials used in industry. 

You will most often see aluminum pride abrasives in the form of sandpaper. However, aluminum oxides are also used in sanding blocks, grinding wheels, and aluminum oxide sanding belts.


Zirconia Poder on a Lab Spoon

Zirconia Poder on a Lab Spoon

Zirconium abrasives offer three significant advantages. They are heat resistant, stronger than most other types of abrasive, and self-sharpening. Because of these characteristics, they are very durable.

Because of their durability, they are ideal for use in manufacturing stainless steel and other hard alloys.

Manufacturers use zirconia to make sandpaper, grinding stones, and sandblasting compounds. In addition, many companies use these materials in flapper wheels and sanding belts. Zirconium Oxide sandpaper comes in grits ranging from 24 to 180.

Zirconia vs. Aluminum Oxide: Used For

Aluminum Oxide Abrasives

You will see three colors of Aluminum oxide grains; white, pink, and brown. Each color has characteristics making it best suited for particular purposes. 

White Aluminium Oxide– White aluminum oxides best suit smooth painted surfaces and softwoods. However, it wears quickly and is not very aggressive.

Pink Aluminium Oxide– Pink aluminum oxide is slightly more durable than white but still relatively soft. 

Brown Aluminum Oxide– Brown is the most common aluminum oxide abrasive. They generally don’t provide a smooth finish, but their abrasive grain cuts faster. Even with a finer grit, they are more aggressive. 

Zirconia Material

You will often see them used in auto refinishing and industries that work with:

  • Tungsten
  • Carbon steel
  • Stainless steel
  • Titanium
  • Tool steel
  • Cast iron

Zirconia and Aluminum Oxide How Do They Differ

Different Forms Abrasives You Can Find Abrasives In

Different Forms Abrasives You Can Find Abrasives In

Alumina-based and zirconia-based material systems differ in many ways primarily because of the chemical makeup of their base materials. Zirconium is a crystalline metal with a hardness of 8.5 on the Mohs Scale. For reference, diamonds are a 10.

In contrast, aluminum has a hardness of only 2.8 Mohs. 

In plain language, zirconia is much more complicated. It cuts rather than deforms, and its crystals fracture into new sharp points as used. Aluminum, being softer, tends to wear faster but cuts more gently.

Zirconia vs. Aluminum Oxide – Which Should You Choose

Man Polishing Steel with an Orbital Sander

Man Polishing Steel with an Orbital Sander

When deciding which abrasive to use, it is best to consider the scope of your project. For large projects, the durability of zirconium oxide is a definite advantage. You could say the same for working on hard materials. 

Then again, if you’re smoothing a minor area or working on spruce, aluminum, or similar materials, the aluminum oxide will work. It can also be a better choice when you desire a higher luster.

While the hardness and long service life of zirconia are a plus, they come at higher costs. They can also be harder to find. Finally, budget is always a consideration. 

Aluminum oxide is much more readily available and much less expensive. For this reason, it is the go-to abrasive for most general consumers. 

General applications:

Zirconium Oxide

Aluminum Oxide


Both zirconia and aluminum oxide abrasives are essential in industry and home use. Zirconium oxide has a definite edge for rough stock removal or working with hard materials. Alumina is probably a better choice for a smoother finish and softer surfaces. For more information or any questions, feel free to contact us.

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