1. Materials and Equipment
Core materials: Cerium oxide powder with a purity of ≥99%, particle size 1-5μm (coarse particle size 3-5μm for rough polishing, fine particle size 1-2μm for fine polishing)
Auxiliary materials: deionized water, pH adjuster (NaOH/citric acid)
Tools and equipment: polishing machine (manual or electric), polyurethane/wool polishing pad, stirrer, pH test paper, measuring cup
2. Standard operating procedures
1. Pretreatment
Glass cleaning: degreasing with ethanol/acetone, ultrasonic cleaning to remove micron-sized particles
Preparation of polishing liquid: stir into a uniform suspension according to the ratio of cerium oxide: water = 1:5-10, adjust the pH to 9-11 (alkaline environment accelerates chemical reaction)
2. Polishing operation
Equipment debugging: fix the wet polishing pad, set the speed, 100-300rpm for ordinary glass, 50-100rpm for optical glass
Material loading and polishing: spray slurry, apply 0.1-0.5MPa pressure, use 8-shaped trajectory, and replenish material every 2-5 minutes
Process monitoring: observe the roughness with microscope (target Ra<1μm), and detect the surface error with interferometer (PV<λ/4)
3. Post-processing
Cleaning: rinse with deionized water → wipe with isopropyl alcohol → dry with hot air below 60°C
Quality inspection: light transmittance test (normal glass ≥ 90%), UV light inspection for surface defects
3. Common Problems
Surface fogging: slurry is too concentrated / polishing is too excessive, dilute the slurry and shorten the fine polishing time
Deepening scratches: impurities in the polishing pad / uneven pressure, replace the polishing pad and calibrate the pressure system
Low efficiency: pH deviation / temperature is too low, adjust pH to 10 and preheat the slurry to 25℃