Microblasting, glass bead blasting and sandblasting are effective methods for pretreating surfaces before coating processes. These methods are used to clean, roughen and activate the surface to ensure optimum adhesion of the subsequent coating.

Microblasting uses very fine abrasives with grain sizes in the micrometre range, such as micro glass beads or micro corundum. The use of these fine blasting media enables gentle and precise cleaning and roughening of the surface without excessively attacking the base material. Microblasting is particularly suitable for sensitive surfaces, delicate structures or precision components where a fine and uniform surface topography is required.

Glass beads with grain sizes of typically 50-250 µm are used in glass bead blasting. The glass beads are made of a hard but brittle material and break up into finer particles when they hit the surface. This achieves effective cleaning and roughening without excessively deforming the surface or leaving abrasive residue. Glass bead blasting is suitable for a variety of materials such as metals, plastics or ceramics and creates a clean, matt and reactive surface for subsequent coatings.

Sandblasting uses coarser abrasives such as quartz sand, corundum or steel shot with grain sizes of typically 0.2-2 mm. The use of these abrasives creates stronger removal effects and coarser surface profiles. Sandblasting is suitable for removing thick coatings, rust, scale or impurities and for creating pronounced roughness profiles for improved mechanical anchoring of the coating. However, sandblasting can also lead to deformation or hardening of the surface and leave behind abrasive residue.

In all processes, the time between pre-treatment and coating is of crucial importance. Too long a period of time between blasting and coating can lead to the formation of oxide layers or renewed contamination of the surface, which impairs the adhesion of the coating. The coating should therefore be applied as soon as possible after pre-treatment.

With all blasting processes, the choice of suitable abrasive, the blasting parameters (pressure, angle, distance) and the blasting time are crucial to achieving the desired surface result and avoiding damage to the base material. Post-treatment, such as dedusting and cleaning the blasted surface, is also important to ensure optimum adhesion of the coating.

The choice of the appropriate blasting process depends on the type of base material, the contaminants to be removed and the surface structure requirements. While micro glass bead blasting is suitable for delicate surfaces and finer structures, sandblasting is used for more robust materials and coarser contaminants.

All in all, microblasting, glass bead blasting and sandblasting help to optimally prepare the surface for coating processes. By adapting the blasting process and the blasting parameters to the respective material and the coating requirements, customised surface properties can be achieved that enable high coating quality and long-term stability.