摘要:
The present invention provides polymeric materials arranged as photonic crystals, or portions of photonic crystals, having properties which can be easily tuned over a large range of wavelengths upon exposure to an external stimulus. In some embodiments, the photonic crystals comprise at least one portion which can undergo a change in a physical, chemical, dielectric, or other property upon exposure to an altering stimulus, resulting in a change in a diffracted wavelength of electromagnetic radiation (e.g, light) by the photonic crystal. Embodiments of the invention may advantageously exhibit large stop band tunability and rapid response times. Photonic crystals of the invention may be useful in a wide variety of applications, such as colorimetric sensors, active components of simple display devices, electrically controlled tunable optically pumped laser, photonic switches, multiband filters, and the like.
摘要:
The present invention provides polymeric materials arranged as photonic crystals, or portions of photonic crystals, having properties which can be easily tuned over a large range of wavelengths upon exposure to an external stimulus. In some embodiments, the photonic crystals comprise at least one portion which can undergo a change in a physical, chemical, dielectric, or other property upon exposure to an altering stimulus, resulting in a change in a diffracted wavelength of electromagnetic radiation (e.g, light) by the photonic crystal. Embodiments of the invention may advantageously exhibit large stop band tunability and rapid response times. Photonic crystals of the invention may be useful in a wide variety of applications, such as colorimetric sensors, active components of simple display devices, electrically controlled tunable optically pumped laser, photonic switches, multiband filters, and the like.
摘要:
The present invention provides polymeric materials arranged as photonic crystals, or portions of photonic crystals, having properties which can be easily tuned over a large range of wavelengths upon exposure to an external stimulus. In some embodiments, the photonic crystals comprise at least one portion which can undergo a change in a physical, chemical, dielectric, or other property upon exposure to an altering stimulus, resulting in a change in a diffracted wavelength of electromagnetic radiation (e.g, light) by the photonic crystal. Embodiments of the invention may advantageously exhibit large stop band tunability and rapid response times. Photonic crystals of the invention may be useful in a wide variety of applications, such as colorimetric sensors, active components of simple display devices, electrically controlled tunable optically pumped laser, photonic switches, multiband filters, and the like.
摘要:
A process for continuous composite coextrusion comprising: (a) forming first a material-laden composition comprising a thermoplastic polymer and at least about 40 volume % of a ceramic or metallic particulate in a manner such that the composition has a substantially cylindrical geometry and thus can be used as a substantially cylindrical feed rod; (b) forming a hole down the symmetrical axis of the feed rod; (c) inserting the start of a continuous spool of ceramic fiber, metal fiber or carbon fiber through the hole in the feed rod; (d) extruding the feed rod and spool simultaneously to form a continuous filament consisting of a green matrix material completely surrounding a dense fiber reinforcement and said filament having an average diameter that is less than the average diameter of the feed rod; and (e) depositing the continuous filament into a desired architecture which preferably is determined from specific loading conditions of the desired object and CAD design of the object to provide a green fiber reinforced composite object.
摘要:
The present invention relates to the fabrication of low cost, in situ, porous metallic, ceramic and cermet foam structures having improved mechanical properties such as energy absorption and specific stiffness. Methods of fabricating the structures from compositions including ceramic and/or metallic powders are provided. The flowable compositions also include an immiscible phase that results in pores within the final structure. Furthermore, the structures may be shaped to have external porosity, such as with mesh-like structures.
摘要:
The present invention relates to a low density, water-soluble coring and tooling material used for the fabrication of composite parts. One aspect of the present invention relates to a lightweight, strong composite coring material that can be easily shaped and removed from cured composite parts. Another aspect of the present invention relates to a lightweight, strong composite tooling material that is easily tailored to provide a specific coefficient of thermal expansion and thermal conductivity, thus providing a tooling material that can be matched to the composite structure and material being fabricated.
摘要:
A process for continuous composite coextrusion comprising: (a) forming first a material-laden composition comprising a thermoplastic polymer and at least about 40 volume % of a ceramic or metallic particulate in a manner such that the composition has a substantially cylindrical geometry and thus can be used as a substantially cylindrical feed rod; (b) forming a hole down the symmetrical axis of the feed rod; (c) inserting the start of a continuous spool of ceramic fiber, metal fiber or carbon fiber through the hole in the feed rod; (d) extruding the feed rod and spool simultaneously to form a continuous filament consisting of a green matrix material completely surrounding a dense fiber reinforcement and said filament having an average diameter that is less than the average diameter of the feed rod; and (e) depositing the continuous filament into a desired architecture which preferably is determined from specific loading conditions of the desired object and CAD design of the object to provide a green fiber reinforced composite object.
摘要:
The present invention relates to the extrusion freeform fabrication of low cost, in situ, metallic foam components having oriented microstructures and improved mechanical properties such as energy absorption and specific stiffness. The present invention relates to the freeform fabrication of metallic foams to form parts having complex geometry that demonstrate superior mechanical properties and energy absorbing capacity.