INFORMATION ABOUT STAINLESS STEEL SANDBLASTING
You can find information and explanations about stainless steel sandblasting on this web page. During the production phase of stainless steel vary according to the sectoral needs, so the sandblasting becomes more important. During the production of stainless steel products, sandblasting is to be preferred in order to resolve manufacturing defects as a matter of priority. Stainless steel sandblasting is also used for providing the desired surface texture, for increasing strength and for surface cleaning.
The texture of the blasted surfaces vary with the blast media. For architectural applications stainless steel shot or glass bead peened finishes are a good choice for getting the good combination of corrosion resistance from a non-directional surface 'sheen' finish. In blasting the impacting medium cuts the steel surface, removing small amounts of metal from the surface. The resulting surface finish and hence surface corrosion resistance of the treated stainless steel is partly dependant on the blasting medium. Very hard media, such as aluminium oxide can leave a jagged or torn faces to metal peaks on the surface, whereas the softer media gives a smoother finish. The aluminium oxide finish can result in reduced corrosion resistance and cleansibility. In contrast, peening a surface does not remove metal. The impact of the rounded bead blasting medium results in small craters in the surface, giving a dimpled appearance, at a suitable magnification, as metal is pushed aside. The edges of these small craters are not however sharp and so the corrosion resistance and cleansibility of peened surfaces compares well with blasted surfaces, for a given steel type and 'roughness' of the surface.
Bead blasting results in a non-directional textured surface with a soft satin reflection and low reflectivity. This process works well when applied over satin or mirror polished finishes. A range of coarsenesses can be created, depending upon the media used and the thickness of the material treated. Unlike acid etching, no material is removed from the surface during the blasting process, but the character of the surfaces produced by these two processes are similar. During peening the surface of austenitic stainless steel is work hardened and surface compressive stresses are induced. There are specific advantages from these surface property changes; Improved fatigue resistance, Increased surface hardness. The finish has enhanced scratch resistantance. Improved stress corrosion cracking resistance of austenitic stainless steels. (for any given steel type and service environment) Abrasive amount and blasting pressure should be controlled in a good way for desired surface texture and the surface quality.
The surface work hardening can however result in distortion. For this reason blast finishes should not be applied to stainless steel thinner than 0.4 mm. To avoid product distortion on thin sections blasting on both sides should be considered.