| 摘要 |
A method of making porous shapes from unit structures such as beads involves coating the beads with two or more layers of material deposited such that it forms an energetic material. These bi-layer energetic materials are formed from a variety of materials including, but not limited to: Ti & B, Zr & B, Hf & B, Ti & C, Zr & C, Hf & C, Ti & Si, Zr & Si, Nb & Si, Ni & Al, Zr & Al, or Pd & Al, all of which can be deposited from vapor. Pressure is applied to prevent the components from moving and the solid-state reaction between the alternating layers produces exothermic heat. Heat from the reaction alone or in conjunction of an applied brazing compound joins the beads forming a porous shape that is desired. The reaction in the materials may be activated with a small pulse of local energy that can be applied using optical, electrical, or thermal sources. Common examples include an electrical pulse, spark, hot filament, a laser beam, etc. The method reduces energy consumption and the need for specialized equipment. The reactive materials and optional brazing material are preferably applied in a fluidized CVD furnace.
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