Basic Technical Parameters Affecting Abrasive Selection

One of the most important factors influencing the quality, efficiency, and cost of a sandblasting process is selecting the right abrasive grit. Inappropriate abrasive type for the surface hardness, process type, desired roughness, and equipment capacity can lead to surface defects, excessive consumption, and wasted time.

Surface Hardness

The choice of abrasive is first made according to the type of material to be sanded:

Material	Recommended Abrasives
Soft metals (Aluminum, Brass)	Garnet, glass ball, basalt, white aluminum oxide, Oxyglass
Medium hard metals	Garnet, nickel slag, basalt, white and brown aluminum oxide, Oxyglass
Hard steel surfaces	Corundum, steel grit, steel ball, nickel slag, brown and white aluminum oxide, silicon carbide, Oxyglass
Casting parts	Steel ball, steel grit, brown aluminum oxide, silicon carbide
Glass / sensitive surfaces	Glass bead, low mesh garnet

Abrasive Hardness

Abrasive hardness is measured on the Mohs scale:

Abrasive	Mohs Hardness Value
Glass Bead	5 – 6
Basalt	6
Nickel Slag	6 – 7
Garnet	7.5 – 8
Corundum	9
Silicon Carbide	9.5
Brown and White Aluminum Oxide	8 - 9
OxyGlass	7 - 8

Grain Size Selection (mesh)

Grain size directly determines surface roughness:

• Small mesh (80 mesh – 120 mesh) → finer surface, delicate work

• Medium mesh (30 – 60 mesh) → general surface preparation

• Large mesh (12 – 24 mesh) → aggressive cleaning, rust and coating removal

Wrong mesh selection:

• Unnecessary consumption

• Paint failure due to high roughness

• It causes problems such as insufficient surface adhesion.

Pressure and Equipment Compatibility Selection

Not every abrasive is compatible with every machine. For example:

• Nickel slag, glass beads and aluminum oxide are more efficient in pressurized systems.

• Steel grit and steel ball are used in turbine systems.

• Garnet provides stable performance in both pressure and injection systems.

  
  

Compressor capacity is also important: Fine-grained garnet or glass spheres are a better choice for low-flow compressors.

Choosing the Right Abrasive Grit is the Foundation of Productivity

The abrasive to be used in the sandblasting process;

• surface type,

• to the desired roughness,

• machine capacity,

• health conditions

• and economic expectations

  
  

should be determined. Choosing the right sand is the most critical factor that directly affects both the quality of the work and the total cost.