Abstract: One embodiment of the invention includes a method of joining two substrates with multilayer thermo-reversible dry adhesives and separating the two bonded substrates by completely thermally reversing the adhesion via heating.

Abstract: One embodiment of the invention includes a multilayer dry adhesive system capable of reversible joining of rigid substrates.

Abstract: A porous polymer sheet or membrane is provided with a thin coating of an electrically non-conductive ceramic composition and the coating conforms to all surfaces, including the pore surfaces, of the membrane. Such a coated membrane serves well, for example, as an intra-cell separator in a lithium ion battery. The coating increases the mechanical properties and thermal stability of the separator in battery operation and retains electrolyte. The coating may be formed by a two-step vapor-phase process in which atoms of one or more metals such as aluminum, calcium, magnesium, titanium, silicon and/or zirconium are deposited in a conformal layer on a workpiece surface. The metal atoms may then be reacted with ammonia, carbon dioxide, and or water to form their respective non-conductive nitrides, carbides, and/or oxides on the surface. The two-step process is repeated as necessary to obtain a ceramic material coating of desired thickness.

Abstract: A welding assembly for forming a weld along a welding interface of a work piece(s) using vibrations includes a welding tool and a thermal barrier. The thermal barrier is at least a chemical and/or mechanical insulating layer positioned adjacent to the welding tool, which minimizes the rate of dissipation of heat generated by the vibrations at or along the welding interface. The welding assembly may also include a wear-resistant layer adjacent to the thermal barrier, which protects the thermal barrier from damage or wear. The welding tool is a portion an anvil assembly and/or a sonotrode assembly. A method of insulating a welding tool includes applying or connecting a thermal barrier to a surface of the welding tool, and minimizing the rate of dissipation of heat generated by the vibrations at or along the welding interface using the thermal barrier, which includes an insulating layer.

Abstract: A method is disclosed for growing metal (including semiconductor metal) nanowires from a film deposited on a substrate. In an illustrative embodiment tin and silicon are co-deposited, such as by sputtering, on a silicon substrate at, for example, ambient temperature. The deposited tin and silicon do not mix and the film has a tin phase dispersed in a higher melting, lower coefficient of thermal expansion, silicon phase. Upon heating, the tin expands against the silicon and expels small tin wires from the upper surface of the film. Other metal or metal alloy wires may be formed in a like manner using a matrix material and substrate in film deposition that don't mix with the metal composition and, when heated, force the expanding metal to extrude from the film surface as small diameter wires.

Abstract: One embodiment of the invention includes a method of joining two substrates with multilayer thermo-reversible dry adhesives and separating the two bonded substrates by completely thermally reversing the adhesion via heating.

Abstract: A method of making at least one nanographene layer is disclosed herein. The method includes selecting X hydrocarbon precursor and Y hydrogen gas (H2) such that a ratio of X/Y ranges from 0.5 to 1, the hydrocarbon precursor including at least one of CH4, C2H2 or C3H8. The method further includes submitting the hydrocarbon precursor to chemical vapor deposition using the hydrogen gas and argon gas (Ar). As a result, i) the hydrocarbon precursor reacts with the hydrogen gas and argon gas (Ar) according to the following reaction: X hydrocarbon precursor+YH2+ZAr?2X graphene+(Y+2X)H2+ZAr, where Z ranges from 5*(X+Y) to 10*(X+Y), and ii) the hydrocarbon precursor decomposes and self-assembles to form the at least one nanographene layer.

Abstract: The performance and durability of static and dynamic seals for hydrogen storage and supply systems has been improved by utilizing a spring-energized and plastic coated radial seal in combination with at least a mating surface that has been treated by one of a variety of procedures. These procedures include applying to the mating surface a low-friction, hard, and hydrogen impervious coating, chemically polishing the mating surface, and electrochemically polishing the mating surface. Each of these procedures significantly reduces, on a microscopic scale, the surface roughness of the mating surface. The seal can thus form a tighter and more gas-tight seal with the smoother mating surface so as to decrease the loss of hydrogen gas across the seal. The smoother mating surface can also improve seal life by reducing seal surface wear.

Abstract: A method of creating adherent, fracture-toughened polycrystalline diamond coatings on carbide cutting tools or other workpiece substrates through the development of composite coatings comprising polycrystalline diamond and carbon nanotubes is described. The coating is deposited through a chemical vapor deposition process using a pre-determined hydrocarbon-hydrogen gas mixture suitable for nucleating diamond on the carbide particles and carbon nanotubes on the metallic binder. The deposited coating, which may be up to 30 micrometers in thickness, is typically characterized by a diamond or diamond-like carbon matrix in which carbon nanotubes are distributed as fiber-like filler materials.

Abstract: A method of creating adherent surface coatings on carbide cutting tools or other workpiece substrates through the development of polycrystalline diamond coatings or composite coatings comprising a refractory metal carbide and polycrystalline diamond is described. The coating is deposited through a sequenced chemical vapor deposition process, first using a specified gas mixture of hydrogen and a refractory metal halide to deposit a base layer of a refractory metal carbide. This step is followed by a second step in which polycrystalline diamond is deposited from a gas mixture comprising a hydrocarbon and hydrogen. Co-deposition of refractory metal carbide and diamond in the second step to create a toughened diamond coating is also contemplated.

Abstract: One embodiment includes a dry adhesive material including catechol chemically attached to the surface of a shape memory polymer molecule. The catechol content may allow the dry adhesive to be utilized in both dry and wet conditions to bond objects together. The shape memory polymer may allow the dry adhesive to be reversibly attached to the objects.

Abstract: One exemplary method includes providing a first polymer and a second polymer each comprising a first shape memory polymer backbone having at least one surface free side chain, the first polymer and the second polymer each transformable between a permanent shape and a temporary shape; creating an adhesive bond between the first polymer and the second polymer, wherein the creating of the adhesive bond transforms the first polymer to its temporary shape and transforms the second polymer to its temporary shape; and wherein the at least one surface free chain of the first polymer in its temporary shape is interdiffused with the at least one surface free chain of the second polymer in its temporary shape by the creation of the adhesive bond.

Abstract: A thermo-reversible dry adhesive, having shape memory polymer characteristics, introduces one or more particles of micro- or nano-particles to at least one layer of the at least one layer of shape memory polymer. These particles may be remotely activated to induct heat sufficient to transform the dry adhesive material from its temporary shape to its permanent shape in the absence of load, which allows the dry adhesive to be reversibly coupled to one or more substrates, wherein the degree of adhesion is greater when the dry adhesive is in the temporary shape than in the permanent shape.

Abstract: A method of broaching a hardened steel workpiece with diamond-tipped tools includes forming a polycrystalline diamond insert and finish-grinding the polycrystalline diamond insert. The polycrystalline diamond insert is attached to an insert holder of a broach bar. A gear blank formed from steel is heat treated, and then an interior portion of the heat treated gear blank is broached with the broach bar. The broaching may occur in a single pass. Some embodiments of the method may further include forming the polycrystalline diamond insert by electrical discharge machining. Furthermore, finish-grinding the polycrystalline diamond insert may include grinding with a diamond grinding wheel. Attaching the polycrystalline diamond insert to the insert holder of the broach bar may include brazing.

Abstract: An exemplary embodiment discloses a polymer system including a shape memory polymer material and a graphene material.

Abstract: A polymer material system that consists of multiple SMP layers of different shape memory transition temperatures in a multilayer construction to achieve and tailor a multiple shape memory effect. Wherein two SMP layers of different shape memory transition temperatures are utilized, a triple shape memory effect is achieved.

Abstract: A reversible adhesive system for coupling together two objects may consist of two shape memory polymers with molecular “hooks and loops” on the surfaces (i.e. the surface away from each of the objects). Utilizing the shape memory properties of the polymers, the molecular hooks and molecular loops may be brought together to form non-covalent bonds, leading to macroscopic adhesion. Upon heating, the adhesive bond can be separated with a small peeling force. The adhesive bonding and debonding can be repeated for multiple cycles with significant adhesion retention.

Abstract: An intercalation electrode includes an electron current collector and graphene planes deposited normal to the surface of the current collector substrate. The graphene planes are deposited on the current collector substrate from a carbon-precursor gas using, for example, chemical vapor deposition. In an embodiment of an anode for a lithium-ion battery, the graphene planes are intercalated with lithium atoms. A lithium-ion battery may include this anode, a cathode, and a non-aqueous electrolyte. In repeated charging and discharging of the anode, lithium atoms and ions are readily transported between the graphene planes of the anode and the electrolyte.

Abstract: One exemplary embodiment includes a thermo-reversible polymer adhesive including a dry adhesive layer and shape memory polymer layer, the shape memory polymer material capable of transitioning from a first shape to a second shape upon heating and imposition of a load to conform to the surface topography of a substrate to which the adhesive is applied.

Abstract: A method of depositing nanocrystalline diamond film on a substrate at a rate of not less than about 0.2 microns/hour at a substrate temperature less than about 500° C. The method includes seeding the substrate surface with nanocrystalline diamond powder to an areal density of not less than about 1010sites/cm2, and contacting the seeded substrate surface with a gas of about 99% by volume of an inert gas other than helium and about 1% by volume of methane or hydrogen and one or more of acetylene, fullerene and anthracene in the presence of a microwave induced plasma while maintaining the substrate temperature less than about 500° C. to deposit nanocrystalline diamond on the seeded substrate surface at a rate not less than about 0.2 microns/hour. Coatings of nanocrystalline diamond with average particle diameters of less than about 20 nanometers can be deposited with thermal budgets of 500° C.-4 hours or less onto a variety of substrates such as MEMS devices.