Surface Treatment: Polishing

      Polishing is a surface treatment method to modify the surface of parts. Generally, it can only obtain smooth surfaces, and can not improve or even maintain the original processing accuracy. With different pre-processing conditions, the Ra value after polishing can reach 1.6 ~ 0.008 um. according to different implementation principles, it can be divided into mechanical polishing and chemical polishing.

Wheel polishing：

       The workpiece surface is polished by rolling and micro cutting with high-speed rotating flexible polishing wheel and very fine abrasive. The polishing wheel is made of multi-layer canvas, felt or leather, which is used for polishing larger parts.

Drum polishing and vibration polishing：

      Put the workpiece, abrasive and polishing fluid  into the drum or vibration box. The drum rolls slowly or the vibration box vibrates, so that the workpiece and workpiece, workpiece and abrasive rub against each other. Combined with the chemical action of polishing fluid, the oil stain and rust layer on the workpiece surface are removed, and the convex peaks are removed, so as to obtain a smooth surface. It is used for polishing small size but large quantity parts. The latter has higher productivity and better polishing effect than the former.

chemical polishing: 

        The metal parts are immersed in a special chemical liquid, and the phenomenon that the dissolution speed of the convex part of the metal surface is faster than that of the concave part is used to realize the polishing of the part surface.