Dynetics, Inc.

Other

James L Maxwell

Nicholas Webb

James Allen

Joseph Pegna

The disclosed methods and apparatus improve the fabrication of solid fibers and microstructures. In many embodiments, the fabrication is from gaseous, solid, semi-solid, liquid, critical, and supercritical mixtures using one or more low molar mass precursor(s), in combination with one or more high molar mass precursor(s). The methods and systems generally employ the thermal diffusion/Soret effect to concentrate the low molar mass precursor at a reaction zone, where the presence of the high molar mass precursor contributes to this concentration, and may also contribute to the reaction and insulate the reaction zone, thereby achieving higher fiber growth rates and/or reduced energy/heat expenditures together with reduced homogeneous nucleation. In some embodiments, the invention also relates to the permanent or semi-permanent recording and/or reading of information on or within fabricated fibers and microstructures. In some embodiments, the invention also relates to the fabrication of certain functionally-shaped fibers and microstructures. In some embodiments, the invention may also utilize laser beam profiling to enhance fiber and microstructure fabrication.

Method and apparatus for fabricating fibers and microstructures from disparate molar mass precursors

Method and apparatus for the selective heat-induced deposition of solid material from gas-phase or super-critical fluids to produce three-dimensional parts by pyrolysis of the fluids. The apparatus involves computer/feedback control of the evolving shape by direct monitoring of the volumetric deposition rate or growth profile, and modifying light beam focal properties, the position and orientation of the deposit relative to the beam foci, and/or the pressure and flow of reactants to the growth zone. The precursor gases may be pressurized and heated to the critical point or beyond, becoming super-critical fluids, without condensation. Growth occurs by diffusion of reactants to the growth zone through a boundary layer over the deposit. One method of growth includes directing a large-area impinging jet of precursor fluid(s) onto a deposit interface, while limiting the reaction zone to a smaller area determined solely by size of the heated zone (through use of a radiant beam, e.g.). Another method comprises directing a small-area impinging jet of precursor fluid onto a deposit interface, where the heated region is larger than the jet size. Inclusion of a powder admixture and a precursor as a reactant, flowed jointly at high-pressures, create a two-phase flow, facilitated by increased viscosity of precursor fluid at high pressures. The powder may also be flowed separately, and adds volume and properties to the deposit material. Thus, the invention allows continuous growth of single- or multi-material, three-dimensional microstructures with internal features and characteristic dimensions from microns to decimeters.

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Scottsboro, AL, United States of America

James L Maxwell