| 摘要 |
Methods for making fiber-reinforced carbon, ceramic or metal matrix composites using electrophoretic infiltration of an array or preform of electrically insulating fibers positioned adjacent a target electrode in an appropriate liquid slurry. The slurry contains a dispersion of micron- or submicron-sized particles, usually of elemental or ceramic materials, which are suitably electrically charged in the slurry, employing a surfactant if necessary. Application of an appropriate voltage causes charged particles to migrate toward the target electrode following a path that causes them to infiltrate the interstices of the fiber array which is usually formed of woven or aligned tows of minute fibers about 5 to 15 microns in diameter. The particles initially deposit on the electrode with subsequent particles aggregating on top of those particles, the process continuing to form a growth front of deposited material growing away from the electrode surface. The resultant deposit of aggregating particles grows through the interstices of the fibrous preform from one surface of the preform to the other, filling voids with matrix material. Following such infiltration, the impregnated particles are consolidated by hot-pressing and/or by subjection to CVI.
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