An improved hybrid composite projectile barrel comprising an inner liner and an outer composite matrix, the inner liner having a breech transition region and a muzzle transition region. The breech transition region and the muzzle transition region each comprises locking features that secure the outer composite matrix to the inner liner at the transition regions. In a first embodiment, the locking features are a series of longitudinally extending ribs with notches. In a second embodiment, the locking features are a plurality of pins disposed around the circumference of the breech and muzzle transition regions. In a third embodiment, the ridges and pins are combined such that a pin extends from the top of each ridge. In each embodiment with pins, the height of the pins is preferably adjusted so that the top ends of the pins form a line that is parallel with the outer diameter of the inner liner.
A composite multi-lobe barrel is disclosed for directing the path of a dischargeable projectile. The multi-lobe barrel incorporates a plurality of longitudinal stiffening rods into a composite overwrap around an inner liner to enhance axial stiffness. The barrel is comprised of an inner liner defining an axial bore; a plurality of polymer matrix composite (PMC) stiffening rods equidistantly disposed around the inner liner and a PMC outer shell enclosing the stiffening rods. In one embodiment, a PMC inner wrap surrounds and is in direct contact with the inner liner, with the stiffening rods arranged equidistantly around the inner wrap, with this structure enclosed by a PMC outer shell.
A composite projectile barrel is disclosed comprising a continuous fiber composite outer shell whose average effective coefficient of thermal expansion in the longitudinal direction approximately matches that of an inner liner. In one embodiment, the composite barrel comprises PAN precursor carbon fiber and a thermoset epoxy resin, with the carbon fiber wound at varying winding angles to form a plurality of regions within the outer shell. The finished barrel exhibits light weight, superior axial stiffness and strength, durability, and is reliably accurate.
A composite barrel assembly for a gun, such as a muzzle-loading mortar for fin- stabilized projectiles. The composite construction of the barrel has a plurality of generally concentric layers built-up around a rigid supporting liner which may be fabricated from any of several metal or ceramic compositions. An inner thermal barrier coating of inorganic glass, metal refractory alloy, chromium alloy, functionally graded material or ceramic is disposed within the liner. An overwrap layer of continuous fibers embedded in a matrix surrounds the liner. The matrix is either a resin, polymer, ceramic, glass or metal. An outer shell of continuous fibers embedded in a high temperature polymer matrix surrounds the overwrap. When the liner is made from a metal-based composition, an outer thermal barrier coating may be applied in between the liner and the overwrap.
A composite barrel assembly for a gun, such as a muzzle-loading mortar for fin-stabilized projectiles. The composite construction of the barrel has a plurality of generally concentric layers built-up around a rigid supporting liner which may be fabricated from any of several metal or ceramic compositions. An inner thermal barrier coating of inorganic glass, metal refractory alloy, chromium alloy, functionally graded material or ceramic is disposed within the liner. An overwrap layer of continuous fibers embedded in a matrix surrounds the liner. The matrix is either a resin, polymer, ceramic, glass or metal. An outer shell of continuous fibers embedded in a high temperature polymer matrix surrounds the overwrap. When the liner is made from a metal-based composition, an outer thermal barrier coating may be applied in between the liner and the overwrap.
A composite projectile barrel is disclosed comprising a continuous fiber composite outer shell whose average effective coefficient of thermal expansion in the longitudinal direction approximately matches that of an inner liner. In one embodiment, the composite barrel comprises PAN precursor carbon fiber and a thermoset epoxy resin, with the carbon fiber wound at varying winding angles to form a plurality of regions within the outer shell. The finished barrel exhibits light weight, superior axial stiffness and strength, durability, and is reliably accurate.
A composite projectile barrel is disclosed comprising a polymer matrix composite outer shell that accommodates higher temperature loading. In one embodiment, the invention comprises an outer shell fabricated from carbon fibers and polyimide resin having a glass transition temperature greater than 500° F. In another embodiment, the resin mixture includes a plurality of sizes of aluminum particles, between about 0.1 microns and 10.0 microns in diameter and of approximately spherical shape, as a thermal conductive additive.
01 - Chemical and biological materials for industrial, scientific and agricultural use
Goods & Services
Polymer resins used in the manufacture of resin or fiber composites; adhesives for industrial use; polymer compositions used in the manufacture of commercial and industrial goods
01 - Chemical and biological materials for industrial, scientific and agricultural use
Goods & Services
Polymer resins used in the manufacture of resin or fiber composites; adhesives for industrial use; polymer compositions used in the manufacture of commercial and industrial goods
44.
Low melt viscosity imide oligomers and polyimides therefrom
The present invention relates to novel imide oligomer compositions, polyimides formed therefrom, and methods for making and using the same. In particular, the invention relates to novel polyimide oligomers comprising 3,3′,4,4′-benzophenone tetracarboxylic dianhydride (BTDA), 2-(3,4-dicarboxy phenyl)-1-phenylacetylene anhydride (PE), and a mixture of 1,3-diaminobenzene and 4,4′-(1,3-phenylenediisopropylidene) bisaniline. The polyimide oligomers demonstrate low melt viscosity (these resins are melt processable) while retaining exceptional thermo-oxidative stability, high glass transition temperature, and good mechanical properties in the cured state.
C08G 73/10 - PolyimidesPolyester-imidesPolyamide-imidesPolyamide acids or similar polyimide precursors
C08G 69/26 - Polyamides derived from amino carboxylic acids or from polyamines and polycarboxylic acids derived from polyamines and polycarboxylic acids
This invention provides a continuous process for the growth of vapor grown carbon nanotubes (VGCNT) reinforced continuous fiber preforms for the manufacture of articles with useful mechanical, electrical, and thermal characteristics. Continuous fiber preforms are treated with a catalyst or catalyst precursor and processed to yield VGCNT produced in situ resulting in a highly entangled mass of VGCNT infused with the continuous fiber preform. The continuous process disclosed herein provides denser and more uniform carbon nanotubes and provides the opportunity to fine-tune the variables both within an individual preform and between different preforms depending on the characteristics of the carbon nanotubes desired. The resulting continuous fiber preforms are essentially endless and are high in volume fraction of VGCNT and exhibit high surface area useful for many applications. The invention also provides for composites made from the preforms.
This invention provides a continuous process for the growth of vapor grown carbon fiber (VGCNT) reinforced continuous fiber preforms for the manufacture of articles with useful mechanical, electrical, and thermal characteristics. Continuous fiber preforms are treated with a catalyst or catalyst precursor and processed without vaporization of the preform to yield VGCNT produced in situ resulting in a highly entangled mass of VGCNT infused with the continuous fiber preform. The continuous process disclosed herein provides denser and more uniform carbon nanotubes and provides the opportunity to fine-tune the variables both within an individual preform and between different preforms depending on the characteristics of the carbon nanotubes desired. The resulting continuous fiber preforms are essentially endless and are high in volume fraction of VGCNT and exhibit high surface area useful for many applications. The invention also provides for composites made from the preforms.
B82B 1/00 - Nanostructures formed by manipulation of individual atoms or molecules, or limited collections of atoms or molecules as discrete units
B82B 3/00 - Manufacture or treatment of nanostructures by manipulation of individual atoms or molecules, or limited collections of atoms or molecules as discrete units
B82Y 30/00 - Nanotechnology for materials or surface science, e.g. nanocomposites
