Aluminum Oxide vs. Silicon CarbideApril 07, 2022
Blasting media is essential to product finishing for applications like stripping, cleaning and polishing. Two popular agents — aluminum oxide and silicon carbide — offer sharp cutting for metal and wood finishing alike. Both offer flexibility and overall affordability. So, how do you choose between them?
Aluminum Oxide Abrasives
Aluminum oxide blast media tends to be the most popular choice for use on painted surfaces, wood and most types of metal. These abrasives are also affordable and long-lasting to keep production up at lower costs. Aluminum oxide comes in three colors — pink, white and brown — each with different uses.
Pink and White
The white and pink forms of aluminum oxide create smoother finishes than the typical brown. White is most efficient for processes involving wood and lacquers because it generates less heat and offers exceptional performance in precision applications. Pink works best on softer woods and in sharpening or grinding operations. Their primary drawback is lower durability than the brown varieties.
Brown aluminum oxide, which works best on hard materials, offers affordability and extended wear because its grains take longer to deteriorate. The grits also sharpen themselves as they break, called semifriable grain. Coarser grains wear as they remove larger metal burrs, leaving smoother grains behind for more refined finishes.
Brown aluminum oxide is also highly recyclable, meaning it can handle many blast cycles before needing a replacement. As a result,this option is the most cost-effective blasting abrasive.
Silicon Carbide Abrasives
Like many carbides, silicon carbide blast media is sharp and extremely hard. This toughness makes the abrasive perfect for ceramics, glass, stone, marble, fiberglass and many plastics.
Silicon carbide contains narrow, pointed edges, and you can use it several times without replacement for shorter blast cycles on softer materials. It etches well and prepares the underlying material for finishing coatings. Yet, its hardness can generate faster wear and makes it a less suitable choice for wood or harder metals like steel.
Versatility is the most significant advantage of silicon carbide blasting media. You can use silicon carbide in either direct-pressure or suction-based systems. You can also use it alongside aluminum oxide in finishing operations — the latter for general residue removal and the former for polishing. You’ll save wear on the less durable silicon carbide abrasives while still creating smooth finishes in either individual finishing or blast tumbling.
Silicon carbide is safe for use in wet or volatile environments. It produces no static electricity that can ignite and has very little magnetism. These abrasives offer both friable and nonfriable options to extend the wear.
Get the Blast Media You Need at Finishing Systems
For more information about silicon carbide versus aluminum oxide, turn to the experts at Finishing Systems. Whether you need total affordability or harder abrasives for polishing, we have the solution. We offer both blasting media and choices between friable, semi-friable and standard varieties for maximum versatility.
Contact a knowledgeable team member at Finishing Systems with questions or to request a quote.