Apparatus for forming composite structures

A composite structure forming apparatus for ejecting and causing an aerosol generated by scattering brittle material, polycrystalline fine particles in a gas to collide with a substrate at high speed to form a structure made of the brittle material, said apparatus comprising:

• an aerosol generator for generating the aerosol, the aerosol generator including a source of powder of the fine particles;
• a nozzle for ejecting the aerosol;
• and
• a shredder for shredding cohesion of the brittle material fine powder particles in the aerosol;
• wherein said shredder functions to achieve at least one of shredding the brittle material fine particles cohering in the aerosol and preventing cohesion of the brittle material fine particles in the aerosol,
• wherein the shredder is provided with a plurality of introduction sections, and aerosol streams ejected from these introduction sections collide with one another for shredding;
• and
• wherein the apparatus, including the aerosol generator, the nozzle, and the shredder, causes the aerosol to be ejected at such speed that the brittle material, polycrystalline fine particles in the aerosol deform or fracture when they collide with the substrate surface and form a composite structure having compactness of at least 70% on the substrate surface.

An apparatus for forming a composite structure of brittle material on a substrate surface via aerosol deposition, the apparatus comprising:

• an aerosol generator including a source of powder of brittle material, polycrystalline fine particles with an average particle size of 0.1-5 μm, and which generates an aerosol in which the fine particles are scattered in a gas;
• a structure forming chamber with a reduced pressure;
• a nozzle which ejects the aerosol into the structure forming chamber;
• and
• a shredder operatively connected to the aerosol generator, and which shreds the brittle material fine powder particles cohering in the aerosol into substantially primary particles before the aerosol is ejected from the nozzle;
• wherein the apparatus, including the aerosol generator, the nozzle, and the shredder, causes the aerosol to be ejected at such speed that the brittle material, polycrystalline fine particles in the aerosol deform or fracture when they collide with the substrate surface and form a composite structure having compactness of at least 70% on the substrate surface.