The term bead blasting can refer to the process of sandblasting or abrasive blasting, however, in most cases, it refers to the projecting of media in the form of a bead or sphere against a substrate such as stainless steel, aluminum or any material that requires a surface conditioned via blasting.
Most abrasive blasting is done with media that are jagged and leave a “coarser” surface finish. Bead blasting refers to the use of round spherical media that, when impacted against the surface of a part, will leave a more uniform finish caused by the sphere “dimpling” the surface. This process is most often used when a smooth uniform finish is required and the part must have a dull “satin” finish. The use of steel shot in this way is most often for tensile conditioning of the given substrate.
Bead blasting is the process most often used to achieve a surface finish that is both “rough” but consistent. Fine glass bead blasting is commonly used on aluminum parts that need a “dull” or “satin” finish. Coarser glass bead is used to give a uniform “rough” finish while masking any imperfections in the substrate surface.
Other materials such as aluminum oxide, silica carbide, or garnet, even in their finest grits, will leave any substrate it impacts with a much darker “grayer” finish, whereas glass bead blasting allows the substrate to maintain its base color resulting in a whiter or brighter finish.