How to choose the appropriate polishing process according to the characteristics of quartz optical glass?

Quartz optical glass has the characteristics of high purity, high transparency, low expansion coefficient and good chemical stability. When selecting polishing process, these characteristics need to be considered comprehensively to achieve the best polishing effect and surface quality. The following are some methods to select the appropriate polishing process according to the characteristics of quartz optical glass:

Based on high purity and transparency

Selection of fine polishing materials: In order to prevent impurities from polluting the surface of quartz optical glass and affecting its transparency, high-purity polishing materials should be selected. For example, the use of high-purity cerium oxide polishing powder has uniform particles and few impurities, which can effectively remove tiny defects on the glass surface and maintain high transparency of the glass.

Adopt precision polishing equipment: High-precision polishing equipment can provide stable and uniform polishing pressure and rotation speed to ensure the consistency of polishing process, so as to avoid the influence of excessive or insufficient local polishing on the transparency and optical properties of glass. If a polishing machine with automatic pressure control and speed adjustment function is used, the polishing parameters can be accurately controlled.

Based on low expansion coefficient

Controlling polishing temperature: Quartz optical glass is relatively insensitive to temperature changes due to its low expansion coefficient, but it still needs to be controlled during polishing to prevent thermal stress on the glass surface due to too high temperature, which will affect its optical properties. Polishing equipment with cooling system can be used to take away heat by circulating cooling liquid during polishing, and the polishing temperature can be controlled within a suitable range.

Choose a suitable polishing solution: the composition and performance of polishing solution have an important influence on the polishing effect. For quartz optical glass, polishing solution with good heat dissipation and chemical stability should be selected. For example, water-based polishing solution has good heat dissipation effect, and it is not easy to corrode the glass surface, and it can maintain the low expansion coefficient of glass while ensuring polishing efficiency.

Based on good chemical stability

Adopt mild chemical polishing method: Although quartz optical glass has good chemical stability, too strong chemical polishing agent may still cause slight corrosion on its surface and affect its optical properties. Therefore, mild chemical polishing process should be adopted, such as using polishing solution with weak acidity, and polishing time and temperature should be strictly controlled to avoid excessive corrosion.

Combined with mechanical polishing: Due to the high hardness of quartz optical glass, simple chemical polishing may be inefficient. Combining mechanical polishing can improve polishing efficiency and surface quality. For example, the mechanical chemical polishing (CMP) process, through the synergistic effect of mechanical grinding and chemical action, can not only effectively remove the damaged layer on the glass surface, but also use chemical action to reduce the friction during mechanical polishing, reduce the surface scratches and improve the surface smoothness.