Whisker reinforcements and whisker reinforced composites

摘要

1,130,820. Electro-phoretic coating of fine conductive filaments. HORIZONS Inc. April 20, 1967 [May 4, 1966], No.18297/67. Heading C7B. Conductive fine filaments i.e. of diameter 0.4 to 2 mils n10 to 50Á are electro-phoretically coated with short (0.5 to 10 mms) fine (0À1 to 5 Á diameter) single crystal fibres ("whiskers") from a suspension in a liquid, the whiskers deposited being aligned with the filament. The suspension may also include a resin binder and optionally a metal powder e.g. Ag, or the whisker coating may be subsequently impregnated with a resin or metal. The binder may be subsequently burnt out and the product sintered to densify the coating. Non-conductive filaments, e.g. glass, ceramic, or resin, may be pre-coated with metal to make them conductive. Whisker materials mentioned are graphite, Al 2 O 3 (which may be chromized or platinized), TiO 2 , ZrO 2 , BeO, SiC, TiC, B 4 C, TiN, A1N, WB, Si 3 N 4 or metals, and water dispersions are used with dispersing agents such as ammonium tannate. If resins are included in the dispersion an organic solvent also may be present. In examples the filaments coated are fine wires of Cu, W, and Ag. Binder resins employed are epoxy, phenolic, urea-formaldehyde and acrylamide - acrylic acid resins. As shown the filament is fed by rollers through the sides of the tank holding the dispersion, the filament being connected as one electrode and passing above a counter electrode.