METHOD OF MAKING A DUO DENSITY ARTICLE OF SILICON NITRIDE

摘要

A method of making a duo density article of silicon nitride is taught. A first article portion is formed by shaping silicon metal particles into a suitable configuration and nitriding the same. A release agent is applied to selected surfaces of the first article portion. A readily formable encapsolent, having relatively low strength, is applied to the selected surface of the first article portion. The encapsolent is converted to a high strength material. A second article portion of silicon nitride is hot press bonded to a surface of the first article portion which has no encapsolent thereon. The encapsolent is machined to remove portions thereof, the removal of such portions freeing other portions of the encapsolent to be removed as individual segments.