| 摘要 |
<p>A method for molding composite articles or encapsulating an article wherein an article to be encapsulated or molded and a heat curable thermosetting resin are loaded into the cavity of a mold, which has been preheated to the curing temperature of the resin. The mold is then evacuated to a subatmospheric pressure to impose a vacuum on the mold in order to impregnate the article with the resin and to degas the mold contents. The vacuum is thereafter released to burst any gas bubbles remaining in the mold contents. Superatmospheric pressure is then applied to the mold contents to cause the resin to encapsulate the article. The temperature and the superatmospheric pressure conditions are maintained for a time sufficient to partially cure the resin and form a unitary structure which is ejected from the mold. The structure ejected from the mold is subjected to a further heating cycle to completely cure the resin. 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 a high-reliability passivation layer.</p> |
