... , friction disc and sealing rings. Ultrafine Alumina Ceramic Powder Chemical Name Alumina Molecular Formula Al2O3 Molecular ... Applications Ceralumi-997 Electrochip, structure ceramic, electronic ceramic,bioceramic, Advanced Refractory.Ceralumi-99 Structure ceramic, friction disk,vacuum tube, ... friction disk,vacuum tube. Ceralumi-90 Structure ceramic,sealing ring,friction disk,vacuum tube. Storage ...