1.Mechanical polishing Mechanical polishing is a polishing method that removes the polished convex parts by cutting and plastic deformation of the material surface to obtain a smooth surface. Generally, oilstone strips, wool wheels, sandpaper, etc. are used, mainly manual operation, and special parts such as the surface of the rotating body , auxiliary tools such as turntables can be used, and ultra-fine grinding and polishing methods can be used for high surface quality requirements. Ultra-precision grinding and polishing is a special abrasive tool, which is pressed on the surface of the workpiece to be machined in the grinding and polishing liquid containing abrasive, and rotates at high speed. Using this technology, the surface roughness of Ra0.008μm can be achieved, which is the highest among various polishing methods. Optical lens molds often use this method.
Obviously the hemp wheels sold by the company are used for this type of polishing, mainly for medium polishing of stainless steel.
2.Chemical polishing Chemical polishing is to allow the microscopically protruding parts of the material in the chemical medium to dissolve preferentially over the concave parts, thereby obtaining a smooth surface. The main advantage of this method is that it does not require complex equipment, can polish workpieces with complex shapes, and can polish many workpieces at the same time, with high efficiency. The core problem of chemical polishing is the preparation of polishing liquid. The surface roughness obtained by chemical polishing is generally several 10 μm.
3.Electrolytic polishing The basic principle of electrolytic polishing is the same as that of chemical polishing, that is, by selectively dissolving the tiny protrusions on the surface of the material to make the surface smooth. Compared with chemical polishing, the influence of cathode reaction can be eliminated, and the effect is better. The electrochemical polishing process is divided into two steps: (1) Macroscopically flattening the dissolved products and diffusing into the electrolyte, the geometrical roughness of the surface of the material decreases, and Ra>1μm. (2) The anodic polarization is flattened by low light, and the surface brightness is improved, and Ra<1μm.
4.In ultrasonic polishing, the workpiece is placed in the abrasive suspension and placed in the ultrasonic field together, and the abrasive is ground and polished on the surface of the workpiece by the oscillation of the ultrasonic wave. The macroscopic force of ultrasonic processing is small, and it will not cause deformation of the workpiece, but it is difficult to make and install the tooling. Ultrasonic machining can be combined with chemical or electrochemical methods. On the basis of solution corrosion and electrolysis, ultrasonic vibration is applied to stir the solution, so that the dissolved products on the surface of the workpiece are detached, and the corrosion or electrolyte near the surface is uniform; the cavitation of ultrasonic waves in the liquid can also inhibit the corrosion process, which is conducive to surface brightening.
5.Fluid polishing Fluid polishing relies on high-speed flowing liquid and the abrasive particles carried by it to scour the surface of the workpiece to achieve the purpose of polishing. Commonly used methods are: abrasive jet machining, liquid jet machining, hydrodynamic grinding, etc. Hydrodynamic grinding is driven by hydraulic pressure, so that the liquid medium carrying abrasive particles flows reciprocatingly across the surface of the workpiece at high speed. The medium is mainly made of special compounds (polymer-like substances) with good flowability under lower pressure and mixed with abrasives, and the abrasives can be silicon carbide powder.
6.Magnetic grinding and polishing Magnetic grinding and polishing is the use of magnetic abrasives to form abrasive brushes under the action of a magnetic field to grind workpieces. This method has high processing efficiency, good quality, easy control of processing conditions and good working conditions. With suitable abrasives, the surface roughness can reach Ra0.1μm.
Post time: Jun-13-2023