Tips for Choosing Abrasive Blasting Media

Abrasive blasting makes life easier, from the DIY workshop to the factory floor. This versatile process easily removes paint and rust to speed your car restoration project. It also delivers the precision to drill fragile electronic components without damaging the surrounding circuitry. One key to this versatility lies in the abrasive blasting media you choose.

Abrasive Blasting Media Characteristics

The various media available differ in several characteristics, including hardness, density, size and shape. For instance, harder media like silicon carbide generate a greater depth profile. This makes these powders ideal for cutting and deburring. Likewise, denser particles make deeper indentations in a small surface area.

Particle size (alternatively called mesh size) also makes a significant difference. Smaller particles, for instance, deliver extensive surface coverage for rapid cleaning. Larger particles, on the other hand, make deeper indentations and thus prepare surfaces for coating.

Abrasive blasting media can have a round shape, like glass beads, or an angular shape. Round-shaped particles deliver a softer finish, while angular-shaped particles quickly cut through surface contaminants like rust.

Understanding the terminology used to describe blasting media can help you decipher the options. Some of the key terms include:

  • Mesh Size – Mesh size is another way to describe particle size. To determine the size, technicians pass the media through a steel mesh screen. For example, a mesh size of 325 (equal to 44 microns) means that 95 percent of the particles pass through a mesh screen that includes 325 openings in one linear inch of screen.
  • Depth Profile – When you blast an object, the powder particles form small peaks and valleys on the surface as they strike. The depth profile, also known as the anchor pattern, describes the distance from the top of the peak to the bottom of the valley. A deeper profile helps coating to adhere more strongly to the surface.
  • Microns – Particle size and depth profile are typically measured in terms of microns. One micron equals one millionth of a meter.

Abrasive Blasting Media

Choose the Right Media for the Job

The right abrasive blasting media depends on the project. Aluminum oxide will deliver the precision you need for etching and deburring. However, sodium bicarbonate works much more efficiently for delicate cleaning jobs. The following list provides recommendations for common micro abrasive blasting applications.

  • Cutting – A fine stream of abrasive delivers precise control for cutting actions. Good choices include 50 Micron Silicon Carbide Mixture or 50 Micron Aluminum Oxide Blend.
  • Etching – For etching materials like metals, ceramics or glass, a 27 Micron Aluminum Oxide Blend works exceptionally well.
  • Drilling – Micro abrasive blasting allows technicians to drill holes as small as .005 inch without igniting sparks. Good powders to use include 50 Micron Aluminum Oxide Blend and 50 Micron Silicon Carbide Mixture.
  • Peening – For peening, on the other hand, look for round media like 44 Micron Glass Beads. This process helps to improve the material properties of a metal surface. For instance, peening metal surgical instruments removes the shine, thus reducing glare in the operating room.
  • Abrading – Certain projects require a unique finish for later processing. Abrading can quickly polish a surface or make it rough like sandpaper. For blasting media when abrading, choose aluminum oxide or silicon carbide.
  • Deburring – Micro abrasive blasting allows technicians to precisely target the spot to deburr, even on intricate parts. 50 Micron Aluminum Oxide or 50 Micron Silicon Carbide work very well for deburring.
  • Cleaning – The abrasive blasting media to use for a cleaning job depends on the type of cleaning you need to do. For delicate cleaning or conformal coating removal, choose a soft media such as 50 Micron Sodium Bicarbonate. For aggressive cleaning, on the other hand, go with 17.5 Micron Aluminum Oxide Blend or 75 Micron Crushed Glass.

Quality Jobs Require Quality Materials

Airbrasive offer a variety of abrasive powders with proven performance and reliability. We double screen and sieve test all our powders. Then we vacuum pack them to ensure they retain their purity. We will even customize a formula to meet your needs.