Abstract: A powder composition suitable for use in selective laser sintering for printing an object. The powder composition includes a first fraction having a polyetherketoneketone (PEKK) powder having a plurality of particles. The powder composition includes a second fraction having a plurality of siloxane particles that is dry blended with the PEKK powder prior to selective laser sintering of the powder. In some embodiments, the powder composition includes a third fraction of carbon fiber. The powder composition when used in selective laser sintering results in parts with more consistent results and improves process economics.

Abstract: A powder composition suitable for laser sintering for printing a three-dimensional object obtained by pre-heating a raw PEKK to evaporate a liquid solvent in the raw PEKK and the grinding the raw PEKK to form a PEKK powder, the powder composition having a first fraction comprising a polyetherketoneketone (PEKK) powder having a plurality of particles, the plurality of particles having a mean diameter D50 in the range of 30 ?m to 150 ?m. The plurality of particles of the first fraction are substantially non-spherical.

Abstract: A powder composition suitable for use in selective laser sintering for printing an object. The powder composition includes a first fraction having a polyetherketoneketone (PEKK) powder having a plurality of particles. The powder composition includes a second fraction having a plurality of siloxane particles that is dry blended with the PEKK powder prior to selective laser sintering of the powder. In some embodiments, the powder composition includes a third fraction of carbon fiber. The powder composition when used in selective laser sintering results in parts with more consistent results and improves process economics.

Abstract: An assembly (113) for composite manufacture is provided. The assembly comprises a cured resin impregnated reinforcement material (112) comprising a fibre component and a resin matrix component, in which the resin matrix component comprises polyurethane, the assembly having a length to width ratio of at least 5:1, and the assembly defining a longitudinal direction (L) along its length; and a peel ply (116) in contact with the cured resin impregnated reinforcement material (112), the peel ply (116) comprising a woven layer having a plurality of longitudinal fibres (118) extending in the longitudinal direction (L); and a plurality of transverse fibres (120) extending in a transverse direction (T) normal to the longitudinal direction (L); in which the areal density of the plurality of transverse fibres (120) is higher than the areal density of the plurality of longitudinal fibres (118).

Abstract: Pre-impregnated composite material (prepreg) that can be cured/molded to form aerospace composite parts. The prepreg includes carbon reinforcing fibers and an uncured resin matrix. The resin matrix includes an epoxy resin component, polyethersulfone as a toughening agent, a thermoplastic particle component, a nanoparticle component and a curing agent.

Abstract: Provided is a composition for the treatment of fibers, such as PAN precursor fibers. The finish composition includes a polysiloxane; an emulsifier; water; and a dicarboxylic acid having a pKa from 1 to 4, and boiling point from 200 to 400° C. The dicarboxylic acid may have the following formula: where R1 is absent or a saturated or unsaturated, linear or branched, aromatic substituted or unsubstituted, hydrocarbon group; Y1 and Y2 are independently hydrogen, nitrogen, oxygen, sulfur, phosphorus, C1-C6 alkyl group, or an alkoxy group; and X1 and X2 are independently one or more hydrogen atoms, a metal, a quaternary amine, or a hydrocarbon group having up to 6 carbon atoms, the hydrocarbon group being an alkyl group, an alkylene group, or an aromatic group, which may be branched or linear, and may optionally have one or more heteroatoms selected from the group consisting of nitrogen, oxygen, sulfur and phosphorus.

Abstract: A process for layer-by-layer manufacturing a three-dimensional object from a powder and objects made from the same is described. The process includes the step of applying a layer of a powder on a bed of a laser sintering machine. The powder includes polyetherketoneketone. The process further includes the step of solidifying selected points of the applied layer of powder by irradiation using heat energy introduced by a laser having a power L and successively repeating the step of applying the powder and the step of solidifying the applied layer of powder until all cross sections of a three-dimensional object are solidified. L is between 1 W and 20 W. In some embodiments L is between 1 and 10 W. In some embodiments, the powder is recycled PEKK powder. In some embodiments, the powder includes carbon fiber.

Abstract: Acoustic honeycomb structures that include cells in which a friction-locking insertion process is used to locate acoustic barriers within honeycomb cells to provide multiple degree of freedom (MDOF) acoustic liners having a variety of acoustic resonator depths. Solid polymer films are formed into acoustic barrier caps. The acoustic barrier caps are friction-locked and bonded to cell walls at one or more cell depths to form acoustically reflective hard walls that form effective bottom ends for acoustic resonators.

Abstract: An assembly (113) for composite manufacture is provided. The assembly comprises a cured resin impregnated reinforcement material (112) comprising a fibre component and a resin matrix component, in which the resin matrix component comprises polyurethane, the assembly having a length to width ratio of at least 5:1, and the assembly defining a longitudinal direction (L) along its length; and a peel ply (116) in contact with the cured resin impregnated reinforcement material (112), the peel ply (116) comprising a woven layer having a plurality of longitudinal fibres (118) extending in the longitudinal direction (L); and a plurality of transverse fibres (120) extending in a transverse direction (T) normal to the longitudinal direction (L); in which the areal density of the plurality of transverse fibres (120) is higher than the areal density of the plurality of longitudinal fibres (118).

Abstract: There is provide a process for unwinding material from a spool (2) wherein the angle (?) of take off at the first contact point (4) for the unwind is always in the range 0±20°, and wherein the first contact point (4) for the unwind is no more than 600 mm from the axis (3) of rotation of the spool (2). There is also provided an apparatus for the unwinding of material from a spool (2) comprising an axis (3) upon which a spool (2) may be rotatably mounted and a static first contact point (4) for the unwound material positioned no more than 600 mm from the centre of the axis (3), wherein the angle (?) of take off at the first contact point (4) for the unwind is always in the range 0±20°.

Abstract: A system for producing an object from a powder by selective laser sintering. The system includes a chamber and a support platform in the chamber. A spreader applies a layer of powder to a bed surface. An irradiation source irradiates select points in the powdered layer prepared on the support platform. A radiant heater heats at least a portion of the bed surface. A temperature sensor monitors the temperature of select points on the bed surface. A controller adjusts the radiant heater in response to temperature data provided by the temperature sensor.

Abstract: A method for making carbon fiber in which the tensile strength of carbon fiber is increased without dehumidifying the ambient air that enters every oxidation oven in a multiple oxidation oven system. A positive effect on tensile strength is provided when ambient air entering only the first oven in a series of oxidation ovens is dehumidified. In addition, the ambient air entering the last oven is not dehumidified when one or more of the preceding oxidation ovens is operated with dehumidified air.

Abstract: A system and method for identifying test bars formed during a selective laser sintering build. A part cake is formed during a selective laser sintering build. The part cake comprises parts formed from a powder by selective laser sintering and unsintered powder around the formed parts. The parts include test bars for performing material testing. Each test bar includes a plurality of indentations in a first grip section and a second grip section. The plurality of indentations are arranged in a information providing pattern that is adapted to be readable after the test part is removed from the part cake.

Abstract: A process for manufacturing a three-dimensional object from a powder by selective sintering the powder using electromagnetic radiation. The powder includes recycled PAEK. In one embodiment, the powder includes recycled PEKK. In one embodiment, the powder includes first recycle PEKK and second recycle PEKK. In one embodiment, the powder consists essentially of recycled PEKK. The process may include the step of maintaining a bed of a selective laser sintering machine at approximately 300 degrees Celsius and applying a layer of the powder to the bed. The average in-plane tensile strength of the three-dimensional object is greater than that of a three-dimension object manufactured by selective sintering using a powder including an unused PEKK powder.

Abstract: A powder composition suitable for use in selective laser sintering for printing an object. The powder composition includes a first fraction including a plurality of polyaryletherketone (PAEK) particles having a mean diameter less than 30 microns, a second fraction having a plurality of polyaryletherketone (PAEK) particles having a mean diameter greater than 30 microns, and a third fraction having a plurality of carbon fibers. The first fraction and the second fraction are formed by an air classification separation performed on a pulverized powder. After the separation, the first fraction, the second fraction, and the third fraction are blended in a high intensity mixer. The powder composition when used in selective laser sinter results in parts with increased tensile strength and reduced surface roughness, among other improvements, as compared to similar powders omitting the first fraction. The PAEK may include polyetherketoneketone (PEKK).

Abstract: Method for seaming a multi-sectional composite tooling for use in molding large composite structures. The tooling includes at least two tooling sections that are made from quasi-isotropic sheet molding compound. The two tooling sections are seamed together with a scarf plug at the tooling surface. The scarf plug is composed of specially oriented layers of consolidated quasi-isotropic sheet molding compound. The scarf plug is made from the same type of quasi-isotropic sheet molding compound that is used to make the tooling sections.

Abstract: A powder composition suitable for use in laser sintering for printing a three-dimensional object. The powder composition includes a polyaryletherketone (PAEK) powder having a plurality of particles. The plurality of particles having a mean diameter of D50. The composition includes a plurality of carbon fibers having a mean length L50. L50 is greater than D50. The particles are substantially non-spherical. A portion of the carbon fiber is embedded into the particle via high intensity mixing.

Abstract: Acoustic honeycomb structures that include cells in which a friction-locking insertion process is used to locate acoustic barriers within honeycomb cells to provide multiple degree of freedom (MDOF) acoustic liners having a variety of acoustic resonator depths. Solid polymer films are formed into acoustic barrier caps. The acoustic barrier caps are friction-locked and bonded to cell walls at one or more cell depths to form acoustically reflective hard walls that form effective bottom ends for acoustic resonators.

Abstract: A powder composition suitable for laser sintering for printing a three-dimensional object obtained by pre-heating a raw PEKK to evaporate a liquid solvent in the raw PEKK and the grinding the raw PEKK to form a PEKK powder, the powder composition having a first fraction comprising a polyetherketoneketone (PEKK) powder having a plurality of particles, the plurality of particles having a mean diameter D50 in the range of 30 ?m to 150 ?m. The plurality of particles of the first fraction are substantially non-spherical.

Abstract: Pre-impregnated composite material (prepreg) that can be cured/molded to form aerospace composite parts. The prepreg includes carbon reinforcing fibers and an uncured resin matrix. The resin matrix includes an epoxy resin component, polyethersulfone as a toughening agent, a thermoplastic particle component, a nanoparticle component and a curing agent.