Abrasive media serves as the backbone of blasting processes. Its role is indispensable, but what exactly is abrasive media, and why is it so important?

In this blog, we will explore the different types available, their specific applications, and the factors you need to consider when selecting the right media for your project.

What is abrasive media?

Abrasive media refers to materials used to wear away the surface of a workpiece through friction. These materials can be natural or synthetic and come in various forms such as powders, grains, or pre-formed shapes. They are utilised in a wide range of processes including grinding, polishing, cleaning, and surface preparation. The choice of abrasive media can significantly impact the efficiency and quality of the task at hand.

What are the differences between natural and synthetic abrasive media?

Natural abrasives, such as garnet, are mined from the earth. They are best known for their hardness and ability to grind, cut, and polish. Due to their natural origin, they often have irregular shapes and hardness, leading to inconsistent performance. However, despite this, natural abrasives have traits and uses not found in in synthetic abrasives.

In contrast, synthetic abrasives like aluminium oxide are industrially manufactured, which means their composition, hardness, and shape can be precisely controlled to achieve specific performance characteristics. Generally (although not guaranteed every time as it depends on what is being treated and the type of finish that is required), this results in synthetic abrasives providing higher precision, consistency, and efficiency compared to natural abrasives, making them the preferred choice in modern industrial applications.

How is abrasive media used in blasting?

Abrasive blasting, often referred to as sandblasting which is an outdated term, is a technique used to clean, polish, or prepare surfaces by propelling abrasive media at high velocities. This process is fundamental where surface preparation is crucial for subsequent treatments like painting, coating, or bonding.

The abrasive media is loaded into a blasting machine, which typically includes a blast pot, nozzle, and a source of compressed air or pressurised water. The equipment is designed to propel the media at high speeds toward the target surface. Compressed air or pressurised water is used to propel the abrasive media out of the nozzle. The high velocity of the media particles creates significant impact energy, capable of removing surface contaminants, rust, old paint, or other unwanted materials. As the abrasive media strikes the surface, it performs two primary actions: impact and abrasion. The impact force breaks apart and removes surface contaminants, while the abrasive nature of the media scours the surface, providing a clean, rough texture ideal for coating adhesion. The cleaned and roughened surface enhances the bonding properties for paints, coatings, or adhesives. This is especially important in industries like marine, where surface quality directly impacts the longevity and effectiveness of the applied coatings.

Some abrasive media can be collected and reused multiple times, making the process more cost-effective and, in some cases, environmentally friendly. Other media may require proper disposal after use due to contamination and breakdown during blasting.

What are the different types of abrasive media, and how do you choose the right one?

Choosing the right abrasive media is essential for achieving the desired finish, but with so many to choose from it’s not always easy to identify the right blast media for the job.

The choice of abrasive media depends on the specific requirements of the blasting task. Each type of media varies in hardness, shape, and size, impacting the finish and efficiency of the blasting process.

Airblast Eurospray offers abrasives in extra fine, fine, medium, and coarse grades. Most abrasives are available in several grades and each abrasive type can be used for multiple purposes.

We offer the following abrasives:

• Hi-chrome grit
• Steel shot
• Copper slag
• Chilled iron
• Steel grit
• Aluminium oxide
• Glass bead
• Garnet
• Olivine
• Glassia
• Plastic media
• Walnut shell

To read more information about each abrasive, click here to see our Abrasives & Media Brochure.

Understanding how abrasive media works helps appreciate the complexity and effectiveness of blasting methods in achieving high-quality surface finishes. Whether for cleaning, preparing, or finishing, abrasive blasting remains a cornerstone technique in ensuring surfaces are impeccably treated for their intended applications, and choosing the right abrasive media is the first step to doing this.

Not sure which abrasive is right for your job? Contact our sales team for advice on 01778 560650, or alternatively email us at sales@airblast.co.uk.