1results about How to "Reduce surface defect density" patented technology

This invention discloses a differential centrifugation method for separating α-Al₂O₃ nanoparticles based on morphological response differences, comprising the following steps: S1: Dispersing α-Al₂O₃ nanoparticles at a concentration of 0.55 wt% in anhydrous ethanol, and continuously dispersing the particles using an ultrasonic device; S2: Centrifuging the resulting suspension at 10,000–15,000 rpm, discarding the lower precipitate, and retaining the supernatant; S3: Dispersing the supernatant again using ultrasonication under the same conditions as in step S1; S4: Centrifuging the dispersed system at 4,000–7,000 rpm at a medium speed, and collecting the lower precipitate; S5: Repeating the combined process of steps S2–S4 2–3 times, merging all precipitates obtained in the medium-speed centrifugation stage, and obtaining the target α-Al₂O₃ nanoparticles after drying. The particles obtained by this method exhibit higher polishing rates, lower surface roughness, and lower defect density in CMP, which improves density and grain uniformity in ceramic sintering. At the same time, the method has a clear process, adjustable parameters, and strong equipment versatility, and has significant potential for industrial scale-up and engineering applications.