Coating physical removal methods and their respective advantages and disadvantages

       The physical removal of high temperature coatings mainly includes the following methods:



(1) Sand blasting or shot peening: A certain size of steel shot is sprayed on the coating surface of the workpiece at an appropriate pressure and angle, and the coating is peeled off with a tangential force. This is a direct mechanical withdrawal method. The disadvantage is that the steel shot cannot be reused and consumes more.



(2) Grinding: Sandpaper, emery cloth or mechanical grinding with a grinding wheel is suitable for partial removal of the coating.



(3) Sand blowing: Blow irregularly shaped sand to the surface to be treated at a certain speed to remove oxide scale, oil stains and coatings on the surface, and obtain a rough (sharp angle) surface.



(4) Ion bombardment method: The advantage of this method is that thicker oxide scale can be removed.



(5) EDM treatment: The locally damaged coating can be removed.



(6) Finishing process: the coating can be partially or completely removed.



(7) High-pressure water: Use 50MPa high-pressure water as the acceleration power of the abrasive, and cooperate with the dry or wet feeding system to remove various coatings as a whole. The disadvantage is that the equipment needs to be imported and the price is expensive.