Abstract: Described herein are rhenium boride compounds having desirable characteristics for a variety of applications, ranging from abrasives and cutting tools to protective coatings.

Abstract: Osmium, when combined with boron alone, or in combination with rhenium, ruthenium or iron, produces compounds that are ultra-hard and incompressible. These osmium diboride compounds are useful as a substitute to for other super or ultra-hard materials that are used in cutting tools and as abrasives. The osmium diboride compounds have the formula OsxM1-xB2 where M is rhenium, ruthenium or iron and x is from 0.01 to 1, except when x is not 1 and M is rhenium, x is from 0.01 to 0.3.

Abstract: Described herein are rhenium boride compounds having desirable characteristics for a variety of applications, ranging from abrasives and cutting tools to protective coatings.

Abstract: A three-dimensional, tetrahedral truss and its method of construction are provided. The truss comprises a three-dimensionally periodic skeletal array of an interconnected plurality of skeletal-tetrahedric units, the array being in the pattern of the crystallographic structure known as "cubic-diamond" (FIG. 1). Each of the skeletal-tetrahedric units is a skeletal arrangement of elongate members joined in the pattern of an equilateral skeletal tetrahedron (FIG. 4), and is preferably assembled from four hexagonic triplanar-rings (FIG. 4A) being of the form created by joining six bilateral-elements in a closed ring, triplanar pattern (FIG. 3), the bilateral-elements each having equal sides and having an included angle of about 109.degree.28' (FIG. 3).

Abstract: A thin-walled annular shell of high rigidity relative to its unit weight is provided. The wall of the shell is a composite material built up layerwise of glassy alloy strips of high transverse aspect ratio such that each layer is a strip wrapped at a substantially 45.degree. helix with respect to the elongate axis of the shell and with adjacent layers having alternating directions of wrap. Bonding between adjacent layers and between strips within each layer is accomplished in a selected manner such that the composite wall is structurally monolithic for thin-walled applications thereby taking substantially full advantage of the extraordinary strength properties of glassy alloy strip.

Abstract: A thin-walled annular shell of high rigidity relative to its unit weight is provided. The wall of the shell is a composite material built up layerwise of glassy alloy strips of high transverse aspect ratio such that each layer is a strip wrapped at a substantially 45.degree. helix with respect to the elongate axis of the shell and with adjacent layers having alternating directions of wrap. Bonding between adjacent layers and between strips within each layer is accomplished in a selected manner such that the composite wall is structurally monolithic for thin-walled applications thereby taking substantially full advantage of the extraordinary strength properties of glassy alloy strip.

Abstract: An armor-piercing projectile is provided having hardened multi-layers and being relatively simple in design. The projectile includes an axial bore, a continuous strip of metallic glass wound about the core to form for the projectile a laminated body, a generally conical frontal surface, and a transverse rear surface, and a bonding agent for joining the adjacent laminated surfaces.

Abstract: A flywheel is provided for storing rotational energy at high energy densities and which possesses a primary failure mode of delamination. The flywheel is constructed from glassy metal alloy strips having a high specific strength comparable to anisotropic fibers used in high energy density flywheels and, in addition, having isotropic or nondirectional strength properties allowing a fuller utilization of the strength of the material and thereby increasing energy storage capacities. The glassy metal alloy strips are formed into circular layers, and a plurality of layers are joined concentrically to build up the flywheel. Joining between strips and layers is accomplished with bonding means such that a substantially mechanically monolithic composite structure results, by providing a bonding shear strength at least about equal to the specific strength times the density divided by the aspect ratio of the glassy metal alloy strips.

Abstract: A crystalline optical convertor, adapted to improve the efficiency of a resonant cavity of a laser cavity system, includes: neodymium ions used as lasing ions, a host for the neodymium ions which is used as a laser rod, convertor ions, and a crystalline convertor host. The convertor ions are selected from the group consisting of trivalent dysprosium and trivalent samarium. The crystalline convertor host is selected from the group consisting of: yttrium orthovanadate, yttrium phosphate, yttrium arsenate, yttrium chromate, gadolinium orthovanadate, gadolinium phosphate, gadolinium arsenate, gadolinium chromate and combinations thereof in solid solution. The convertor ions act as an activator for the crystalline convertor host. The combination of neodymium ions and neodymium host is arranged separate from the combination of the convertor ions and the convertor host.