Abstract: Method and apparatus for compaction of powder of high density boron nitride, having an initial particle diameter of at least two microns, into a high density crystal aggregate of between 1 mm up to about 1 cm in diameter, the resulting crystal aggregate having a zincblende form, the wurtzite form or mixtures of the zincblende and wurtzite forms. High density aggregates of boron nitride, preferably having particle sizes with diameters at least 2 .mu.m, are placed in a hollow, substantially cylindrical first container of metal, and the first container is surrounded by a fluid-like material of metal or metal powder having a shock wave velocity V. The first container and fluid-like material are placed in a substantially cylindrical second container that is purged of substantially all air and sealed. The second container has a rigid side wall and two rigid end walls.

Abstract: Superconductive structures and a method of forming the same wherein an assembled mass (12) of superconductive particles, or of a mixture of superconductive particles and particles having other properties, are formed into a desired confined configuration and consolidated into a rigid useful unitized body through shock-wave treatment performed at relatively lower temperatures.

Abstract: A method for the implosive consolidation into a solid body of a mass of free particles, which mass consists, selectively, entirely of amorphous particles, or a mixture of amorphous and nonamorphous particles. During the consolidation act, pressure and temperature are controlled in a manner which assures that the consolidated amorphous particles in the solid body exhibit substantially the same amorphous characteristics as those displayed by the unconsolidated, free amorphous particles.