摘要:
A direct vapor deposition (DVD) apparatus and method is taught, that provides a carrier gas flow entraining vapor atoms for the coating of regions on a substrate that are not in line-of-sight. The degree of non line-of-sight (NLOS) coating, hence thickness uniformity around the substrate is a sensitive function of the flow conditions. For a fixed background pressure in the region of deposition, an increase in the uniformity of the coating thickness is accomplished as the flow velocity is reduced. This improvement in uniformity is a result of an increase in the fraction of vapor atoms which deposit in NLOS positions on the substrate such as backside (21) of fiber (65) as indicated by vapor streamlines (51). Vapor impact width (VIW) is the width of the vapor flux impacting on some area of the fiber. Front side coating (FSC) width is the vapor width of atoms impacting on the substrate frontside (22).
摘要:
Methods of making truss-based periodic cellular solids that have improved structural properties and multifunctional design. Many materials (metals, ceramics, glasses, polymers, composites and even semiconductors) can be shaped into cellular, truss-like architectures (405, 406) with open, closed or mixed types of porosity and then very uniformly arranged in controlled, three-dimensional space-filling arrays (272). The truss-like elements (405, 406) do not necessarily have a constant cross section, nor are they necessarily straight or solid throughout. Their cross sections can be circular, square, triangular, I-beam or other shapes of interest depending on multifunctional needs. When bonded together by solid state, liquid phase, pressing or other methods at points of contact, a cellular structure of highly repeatable cell geometry and few imperfections results. The bonds hold the truss elements (405, 406) together in a desired configuration, allow load to be efficiently transferred amongst them and make the resulting structure significantly more rigid when bent, compressed or sheared.
摘要:
Multifunctional cellular metals or other materials (102) for structural applications that are capable of recovering their original undeformed shape and thickness after impact or crushing, i.e., self-healing. Alternatively, they may normally be stored or used in their compressed, i.e., crushed, state and deployed when needed to act as energy absorbing structure or packaging, i.e., deployable energy absorber. Additionally, the multifunctional structures may act as an actuator, capable of providing localized or distributed force and displacement, and related methods of using and manufacturing the same. These active cellular metals or other materials (110) are composites consisting of conventional metal/alloy truss structures or other material components and offer high specific strength and stiffness, but which are also deployable energy absorbers or self-healing smart structures.
摘要:
Plasma deposition apparatus (1) and method that allows metal or nonmetal vapor (6) to be generated by electron-beam evaporation, guides that vapor using a noble gas stream (containing reactive gases in cases of reactive evaporation), ionizes the dense directed gas and vapor stream at working pressures above about 0.0001 mbar using a hollow cathode plasma arc discharge (11), and conveys the ionized vapor and/or gas stream towards the substrate (4) for impact on the surface at energies varying from thermal levels (as low as about 0.05 eV) up to about 300 eV.