高速遠心成形法の成形機構(第2報) : 粒子の沈降速度及び着肉速度の定量的な検討

概要

論文の詳細を見る
Slips of alumina powders with various particle sizes (0.2-0.54 μm) were put into a glass tube and mounted in a high-speed centrifuge with a rotor radius of 120 mm. The centrifuge were operated at 3000-5000 rpm for 1-3 ks. The falling velocity of particles increased in proportion to centrifugal force and to the square of particles size, as predicted by the Stokes' sedimentation law. On the other hand, the velocity decreased dramatically as the concentration of the slip increased. The velocity V of particles in varied concentration φ of slip can be expressed by V=V_0(1-φ/φ_<max>)^<φmax×K> as proposed by Buscall et al. V_0 and k were empirically derived by assuming φ _<max>=0.63 (the closest packing density for green compact). The compacting velocity was estimated by Kynch's theory. The falling flux of particles in the slip can be calculated using the Buscall equation, and the relation between slip concentration and flux (Kynch-plot) drawn. The gradient of Kynch-plot at the slip concentration of 50 vol% showed roughly the compacting velocity.
社団法人日本セラミックス協会の論文
2001-03-01