Organic Powder Coating
Powder organic coating is a surface protection process where dry polymer resin is electrostatically applied to the workpiece and then thermally cured. This forms a sealed, chemically resistant plastic barrier.
Physicochemical Mechanism of Action
A powder organic coating consists of microscopic particles of polymer resin. These are electrostatically charged onto the surface of the workpiece and arranged there. After application, the material is thermally cured, bonding it into a dense, solid film.
Metallurgical Relevance & Risks When Welding
The coating protects the surface from corrosion and chemical attack. However, it can cause problems during the welding process if handled incorrectly. For example, it can decompose in the weld zone if the temperature is too high or the dwell time too long, which can lead to cracks or distortion.
Workshop Practice & Action Guidelines
Before welding the workpiece, the coating must be carefully removed. This is usually done by chemical removers or mechanical methods such as grinding or polishing. It is important to ensure that no coating residue remains in the weld, as this can lead to corrosion or cracking.