| 摘要 |
PURPOSE: To easily and cost-effectively produce hollow spheres having high strength by pyrolyzing the core parts of a foamed polymer coated with a solid layer consisting of a binder, metal and ceramic powder particles and further sintering the same. CONSTITUTION: The foamed material particle 1 of nearly a spherical shape consisting of foamed polystyrol, etc., is coated with a solid powder/binder layer 2 while the particle is agitated in a dispersion within a fluidized reactor. The coated and foamed material particle 1 is pyrolyzed under agitation at 400 to 500 deg.C after drying, by which the layer 2 is formed to a shell 3 enclosing a cavity 4. Further, the particle is heat treated under agitation at 1000 to 1500 deg.C, by which a sintered layer 5 is formed. At this time, ceramics and/or metallic materials sized 0.0001 to 0.2 mm are used as the powder particles and polyacrylate, cellulose ester, etc., are used as the org. binder. |
