| 摘要 |
A method for encapsulating an electrical component or forming a resin based filler reinforced composite article which comprises providing a rigid mold having a cavity and an opening in one surface of the mold connected to the cavity, and a chamber in which the mold is placed for applying heat and varying pressure to the mold contents. The chamber is preheated to the curing temperature of the resin and is maintained at this temperature. The component or filler is loaded into the mold cavity and the mold is placed in the preheated chamber. Then the mold cavity is filled with a low viscosity heat curable, thermosetting resin such as an epoxy resin. Next, the mold cavity is evacuated to a subatmospheric pressure to impose a vacuum on the mold to impregnate the component or filler with the resin, degas the mold cavity contents, and expand any voids in the resin. The vacuum is released to atmospheric pressure to collapse any gas bubbles remaining in the mold contents. Then, a superatmospheric pressure is applied to the mold to burst any gas bubbles and cause the resin to compact and encapsulate the component or filler. The temperature and the superatmospheric pressure are maintained for a time sufficient to partially cure the resin and form a unitary structure which can be ejected from the mold. The ejected structure is then subjected to further heating to completely cure the resin. The method may be performed in cyclic fashion to form continuously in sequence a plurality of encapsulated components or composite articles. Composite articles so formed are useful as structures, such as antenna waveguides, for space applications. Electrical components encapsulated by the process of the present invention have high voltage resistance.
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