摘要:
The present invention provides an inexpensive, open cell, mechanically robust and graphitizable foam preform. The graphitizable foam is produced via a modified standard flower foam formulation. The invention provides a modified formula for such flower foams wherein a mesophase material is incorporated along with a corresponding reduction in the resole component. The mesophase material replaces 30-70% by weight (a target of 50% by weight) of the resole component of the formulation. The formulation is heated to effect foaming of the mixture, and then carbonized to produce an open cell, graphitizable foam preform.
摘要:
The present invention provides an inexpensive, open cell, mechanically robust and graphitizable foam preform. The graphitizable foam is produced via a modified standard flower foam formulation. The invention provides a modified formula for such flower foams wherein a mesophase material is incorporated along with a corresponding reduction in the resole component. The mesophase material replaces 30-70% by weight (a target of 50% by weight) of the resole component of the formulation. The formulation is heated to effect foaming of the mixture, and then carbonized to produce an open cell, graphitizable foam preform.
摘要:
A carbon-carbon composite material is made by providing an open-celled carbon foam preform, and densifying the preform with carbonaceous material. The open-celled carbon foam preform may be oxygen stabilized prior to carbonization, and the foam preform densified by CVD, HIP, PIC, VPI, pitch and resin injection, or any combination thereof. The carbon-carbon composite material can be heat treated to provide thermal management materials, structural materials, or a friction material for use in a brake or clutch mechanism.
摘要:
A mesophase pitch material having a melting point in excess of 350° C. has a solvent added thereto to provide a solvated mesophase pitch. A low molecular weight solvent is used so that the melting point can be brought low enough to create a carbon foam at a convenient temperature. The solvent is then removed by heat and/or vacuum and, consequently, the pitch reverts to a high melting point of approximately greater than 350° C. The pitch can then be heated or carbonized without an oxidative stabilization step. Alternatively, a solvated mesophase pitch material may be used initially for foaming.
摘要:
Annular brake disc preform (15), wherein 40 to 80 layers of reinforcement fibers of at least two different lengths (11, 19) ranging from 10–60 mm are distributed in a planar gradient throughout the body of the preform, with the reinforcement fibers located near the exterior planes of the disc being predominately shorter fibers (11) and with the reinforcement fibers located in the central planes of the disc being predominately longer fibers (19). Also, process of making carbon-carbon composite preforms by: providing chopped pitch or PAN fibers (11, 19) of at least two different lengths; directing a robotic spraying apparatus to spray the chopped fibers into an annular mold (5) in 40 to 80 concentric iterations of chopped fiber deposition to provide a matrix of fibers in the mold; depositing a curable binder into the mold to intermix the binder with the fiber matrix; compressing the fiber matrix and curable binder within the mold; curing the binder to form a preform matrix; filling the preform matrix with pitch to form a pitch matrix; and subjecting the pitch matrix to chemical vapor deposition to form a carbon-carbon composite preform (15).
摘要:
A carbon-carbon composite material is made by providing an open-celled carbon foam preform, and densifying the preform with carbonaceous material. The open-celled carbon foam preform may be oxygen stabilized prior to carbonization, and the foam preform densified by CVD, HIP, PIC, VPI, pitch and resin injection, or any combination thereof. The carbon carbon composite material can be heat treated to provide thermal management materials, structural materials, or a friction material for use in a brake or clutch mechanism.
摘要:
A resin transfer molding (RTM) process is disclosed for rapidly filling a fibrous preform and/or a rigid, porous body with high viscosity resin or pitch. The process is suitable for impregnated multiple porous bodies stacked in a single mold. The process uses a fibrous preform or rigid porous body which is placed into a mold matching the desired part geometry. A resin is injected into the mold at temperature and pressure. After cooling, the infiltrated component is removed from the mold. The mold is constructed from two halves fitted to form at least one mold cavity. A gate fitted with a nozzle is set into one of the mold halves, and a valve admits resin or pitch into the gate area. Venting or vacuum can be applied to the mold. The mold is held in a hydraulic press and an extruder, optionally fitted with an accumulator, supplies molten resin or pitch to the mold.
摘要:
A resin transfer molding (RTM) process is disclosed for rapidly filling a fibrous preform and/or a rigid, porous body with high viscosity resin or pitch. The process is suitable for impregnated multiple porous bodies stacked in a single mold. The process uses a fibrous preform or rigid porous body which is placed into a mold matching the desired part geometry. A resin is injected into the mold at temperature and pressure. After cooling, the infiltrated component is removed from the mold. The mold is constructed from two halves fitted to form at least one mold cavity. A gate fitted with a nozzle is set into one of the mold halves, and a valve admits resin or pitch into the gate area. Venting or vacuum can be applied to the mold. The mold is held in a hydraulic press and an extruder, optionally fitted with an accumulator, supplies molten resin or pitch to the mold.
摘要:
A carbon-carbon composite material is made by providing an open-celled carbon foam preform, and densifying the preform with carbonaceous material. The open-celled carbon foam preform may be oxygen stabilized prior to carbonization, and the foam preform densified by CVD, HIP, PIC, VPI, pitch and resin injection, or any combination thereof. The carbon-carbon composite material can be heat treated to provide thermal management materials, structural materials, or a friction material for use in a brake or clutch mechanism.
摘要:
An aircraft brake piston housing (10) has a composite body (14) including a plurality of fibers embedded in a matrix, the body (14) including a central bore (18) and a plurality of circumferentially disposed openings (23) surrounding the bore (18), at least some of the circumferentially disposed openings (23) being configured to receive a brake piston (26), and a frame (12) embedded in the composite body (14) and formed from a material different than the matrix. Also a method of forming such a brake piston housing.