What are the polishing methods of aluminum alloy die casting?
Aluminum alloy die-casting mechanical polishing is to get smooth surface polishing method by cutting, plastic deformation of material surface to remove the convex part after polishing, generally using whetstone strip, wool wheel, sandpaper, etc., mainly manual operation. The method of super finishing polishing can be adopted for those with high surface quality requirements. Super finishing polishing is a special abrasive tool that is pressed tightly on the processed surface of aluminum alloy die casting in the finishing liquid containing abrasives for high-speed rotating motion.
1. Mechanical polishing
Aluminum alloy die-castingMechanical polishing is a polishing method to obtain a smooth surface by cutting and removing the convex part after polishing due to plastic deformation of the material surface. Generally, oilstone strips, wool wheels, sandpaper, etc. are used, and manual operation is the main method. If the surface quality requirements are high, the method of super precision polishing can be used. The super precision polishing is to use a special abrasive tool, which is tightly pressed on the machined surface of aluminum alloy die castings in the polishing liquid containing abrasives for high-speed rotation p>
2. Chemical polishing
For aluminum alloy die casting, chemical polishing allows the convex part of the surface of the aluminum alloy die casting to dissolve preferentially in the chemical medium, so as to obtain a smooth surface. The main advantage of this method is that it does not require complex equipment, and it can polish aluminum alloy die castings with complex shapes, and it can polish many aluminum alloy die castings at the same time, with high efficiency. The core problem of chemical polishing is the preparation of polishing liquid, and the surface roughness obtained by chemical polishing is generally 10 μ m。 p>
3. Electrolytic polishing
The basic principle of electrolytic polishing for aluminum alloy die casting is the same as that of chemical polishing, that is, the selective dissolution of the small protruding parts on the surface of the material makes the surface smooth. Compared with chemical polishing, it can eliminate the influence of cathodic reaction, and the effect is better p>
4. Ultrasonic polishing. Ultrasonic machining has small macro force and will not cause deformation of aluminum alloy die castings, but it is difficult to make and install 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 to separate the dissolved products on the surface of aluminum alloy die castings, and the corrosion or electrolyte near the surface is uniform; The cavitation effect of ultrasonic wave in liquid can also inhibit the corrosion process, which is conducive to surface brightening p>
5. Fluid polishing
Aluminum alloy die-castingFluid polishing is to achieve the purpose of polishing by scouring the surface of aluminum alloy die-casting pieces with high-speed flowing liquid and abrasive particles carried by it. Common methods include abrasive jet machining, liquid jet machining, hydrodynamic grinding, etc. Hydrodynamic grinding is driven by hydraulic pressure to make the liquid medium carrying abrasive particles flow back and forth across the surface of aluminum alloy die-casting pieces at a high speed. The medium is mainly fluid under low pressure It is made of good special compound (polymer like material) mixed with abrasive, and the abrasive can be silicon carbide powder p>
6. Magnetic abrasive polishing
Magnetic abrasive polishing is to use magnetic abrasive to form abrasive brush under the action of magnetic field to grind aluminum alloy die castings. This method has high processing efficiency, good quality, easy control of processing conditions, and good working conditions. With proper abrasive, the surface roughness can reach Ra0.1 μ m。 p>