Mechanical polishing process of silicon carbide disc: laying the foundation for high-quality surface- Trojan (Suzhou) material technology Co., Ltd.

In the field of high-tech materials, silicon carbide (SiC) has become the preferred material in many high-end applications due to its excellent physical and chemical properties, especially its extremely high hardness. Especially in occasions requiring high precision and high wear resistance, such as precision machinery, aerospace, semiconductor manufacturing and other fields, silicon carbide discs play an indispensable role. However, the high hardness of silicon carbide also brings great challenges to its processing, especially surface polishing.

Mechanical polishing, as the first process of silicon carbide disc polishing, is of self-evident importance. After the initial forming of silicon carbide discs, there are often defects such as rough layers, micro cracks, and pores on the surface. These defects not only affect the appearance, but may also cause performance degradation or even failure during use. Therefore, removing these surface defects through mechanical polishing to achieve a smooth and flat surface is the key to improving the overall performance of silicon carbide discs.

The core of mechanical polishing lies in the friction between the polishing wheel and the workpiece surface. Therefore, choosing the right polishing wheel material, adjusting the right speed and applying appropriate pressure are the key to ensuring the polishing effect.
Polishing wheel material: The material of the polishing wheel needs to match the hardness of silicon carbide, ensuring sufficient cutting force to remove the surface rough layer while avoiding excessive damage to the workpiece. Common polishing wheel materials include superhard materials such as diamond and cubic boron nitride (CBN), which can act on the surface of silicon carbide efficiently and accurately.
Speed and pressure: The speed and pressure of the polishing wheel are important factors affecting the polishing effect. Too high a speed may cause the polishing wheel to wear too quickly and increase the thermal stress on the workpiece surface; too low a speed may not effectively remove the surface rough layer. Therefore, it is necessary to accurately adjust the speed of the polishing wheel according to the material, size and surface condition of the silicon carbide disc. At the same time, applying appropriate pressure is also the key, ensuring sufficient contact between the polishing wheel and the workpiece surface, and avoiding excessive pressure that causes deformation or damage to the workpiece.

Polishing fluid also plays an important role in the mechanical polishing process. It not only lubricates the contact surface between the polishing wheel and the workpiece, reduces frictional heat and wear, but also assists in removing surface microscopic unevenness through chemical reactions or physical actions.
Polishing liquid composition: The composition of the polishing liquid needs to be carefully selected according to the material characteristics of silicon carbide. Generally speaking, the polishing liquid should contain an appropriate amount of abrasives, surfactants, buffers and other ingredients. Abrasives are used to directly act on the surface of silicon carbide to remove the rough layer; surfactants help reduce surface tension and improve polishing efficiency; buffers are used to adjust the pH of the polishing liquid to protect the surface of the workpiece from corrosion.
Polishing liquid use: When using the polishing liquid, its concentration, temperature and flow rate and other parameters must be strictly controlled. Too high a concentration may cause the polishing liquid to be too viscous and affect the polishing effect; too low a concentration may not fully play its role in lubrication and auxiliary polishing. Temperature control is also important. Too high a temperature may cause the components in the polishing liquid to decompose or fail. The flow rate should be adjusted dynamically according to the speed of the polishing wheel and the surface condition of the workpiece.

Mechanical polishing is a complex and delicate process that requires strict control of the process parameters of each link to ensure the consistency and stability of the polishing effect.
Process design: Design a reasonable polishing process according to the material, size and surface requirements of the silicon carbide disc. Generally, it includes three stages: rough polishing, medium polishing and fine polishing. Different polishing wheels, polishing fluids and process parameters are used in each stage to gradually remove the rough surface layer and improve the surface finish and flatness.
Online monitoring and feedback: During the polishing process, advanced online monitoring technology is used to detect the roughness, flatness and glossiness of the workpiece surface in real time. According to the monitoring results, the parameters such as the speed, pressure and concentration of the polishing fluid of the polishing wheel are adjusted in time to ensure that the polishing effect meets the requirements.
Quality control and evaluation: After polishing, the silicon carbide disc is subjected to comprehensive quality inspection and evaluation. Including the inspection of surface roughness, flatness, glossiness, microstructure and other aspects to ensure that the polishing quality meets the design requirements and use standards.

Mechanical polishing is the first step in the polishing process of silicon carbide discs, and its importance is self-evident. By selecting the right polishing wheel material, adjusting the right speed and applying the right pressure, and using the polishing fluid that matches the characteristics of the silicon carbide material, we can gradually remove the rough layer and microscopic unevenness on the surface of the silicon carbide disc to achieve a smooth, flat and high-quality surface. This process not only lays a solid foundation for the subsequent polishing process, but also improves the overall performance and service life of the silicon carbide disc. With the continuous development of science and technology, we have reason to believe that mechanical polishing technology will play an important role in more fields and contribute more to the processing and application of high-tech materials.