Abstract: A multi-dimensional (e.g., 3D braided) preform formed of reinforcement strands or filaments is rigidized by impregnating the preform with a resin solution (e.g., silicone resin solution), curing the resin to impart a selected shape to the preform and then heating the shaped preform to convert the cured resin to inorganic solids (e.g., silica solids) so dispersed in an effective amount between the strands as to rigidize the preform. The rigidized preform is then infiltrated with an inorganic matrix (e.g., a ceramic material) to form a composite article.

Abstract: A composite gas turbine engine blade is made by braiding a plurality of fibers to form a preform having an airfoil precursor portion and an integral root precursor portion. A plurality of fiber shaping inserts are positioned in the root precursor portion, either by braiding the root precursor portion around the inserts or inserting the fiber shaping inserts into the root precursor portion after braiding, to impart an enlarged, divergent shape (e.g., dovetail precursor shape) to the braided root precursor portion. The braided preform with the enlarged, shaped root precursor portion is infiltrated with matrix material and shaped to near net shape to provide the composite blade with a dovetail shaped root.

Abstract: A coordinate measuring machine is used to extract data points from an airfoil surface. The machine is controlled to move a probe to desired points by a generic program applicable to any airfoil and a nominal data file specific to the type of airfoil being measured containing coordinates of desired data points, surface normal vectors and optional machine control instructions arranged in the order of usage. The program reads the data file and predicts the location of corresponding data points on the surface from the file data and deviation information available from already-sampled data points on the blade. An analysis program accepts the data points, mathematically reconstructs portions of the airfoil and measures dimensions from those portions. The dimensions are compared to tolerances read from another file specific to the airfoil type.

Abstract: A composite gas turbine engine blade is made by braiding a plurality of fibers to form a preform having an airfoil precursor portion and an integral root precursor portion. A plurality of fiber shaping inserts are positioned in the root precursor portion, either by braiding the root precursor portion around the inserts or inserting the fiber shaping inserts into the root precursor portion after braiding, to impart an enlarged, divergent shape (e.g., dovetail precursor shape) to the braided root precursor portion. The braided preform with the enlarged, shaped root precursor portion is infiltrated with matrix material and shaped to near net shape to provide the composite blade with a dovetail shaped root.

Abstract: A braided gas turbine engine blade preform includes an airfoil precursor portion and an integral root precursor portion. A plurality of fiber shaping inserts are disposed in the root precursor portion, to impart an enlarged, divergent shape (e.g., dovetail precursor shape) to the braided root precursor portion. The braided preform with the enlarged, shaped root precursor portion is infiltrated with matrix material and shaped to near net shape to provide a composite blade with a dovetail shaped root.

Abstract: The method involves braiding a plurality of fiber bundles, each comprising a reinforcing fiber overwrapped by a plurality of glass or metal matrix-forming fibers, to form a 3D braided preform having stuffer fiber bundles extending longitudinally therethrough and heating the preform at a temperature and applying pressure to form the matrix-forming fibers into a bonded matrix in which the reinforcing fibers are disposed in a 3D braided pattern and in a longitudinal (stuffer) pattern.

Abstract: The apparatus includes a plurality of fiber strand carrier members that are movable on a carrier surface defined by multiple, movable, side-by-side support members and a plurality of fiber guides affixed on the support members for dispensing axial stuffer fiber strands as the carrier members move along predetermined paths to intertwine the fiber strands from the fiber guides. The carrier members are disposed on the support members for movement therewith and for movement from one support member to abother. The fiber guides are affixed on the support members for movement only with the respective support member. The stuffer fiber strand for each fiber guide is dispensed from a spool that is carried on a respective support member or is mounted on a stationary base.

Abstract: The apparatus includes a plurality of movable support members that are arranged side-by-side and collectively form a quadratic carrier surface, such as a cylindrical carrier surface. A plurality of fiber strand carrier members are movable on the carrier surface to intertwine the fiber strands. Each fiber strand extends from its carrier member along an axis that intersects the axes of the other fiber strands at a generally common consolidation point near a fiber gathering device that gathers the fiber strands from the carrier members. The carrier members are generally equidistant from the fiber consolidation point as a result of moving on the quadratic carrier surface so that the gathering device can maintain a generally constant tension in the fiber strands regardless of their position on the carrier surface.

Abstract: The method involves braiding a plurality of fiber bundles, each comprising a reinforcing fiber overwrapped by a plurality of glass or metal matrix-forming fibers, to form a 3D braided preform having stuffer fiber bundles extending longitudinally therethrough and heating the preform at a temperature and applying pressure to form the matrix-forming fibers into a bonded matrix in which the reinforcing fibers are disposed in a 3D braided pattern and in a longitudinal (stuffer) pattern.

Abstract: An improved method of forming a filamentary reinforced article includes forming a preform of metal and filament layers by winding material around an axis. The resulting layered preform is enclosed in a fluid tight housing. The housing has a rigid frame which bounds the periphery of the preform. The housing also has flexible panel sections which extend inwardly from the frame across the preform. To bond the layers of the preform together and increase the density of the preform, the housing is subjected to a hot isostatic pressing operation. During the hot isostatic pressing operation, fluid pressure forces against the housing plastically deform the panel sections of the housing inwardly in a direction parallel to the axis around which the layers of the preform were wound to apply axial deformation forces to opposite sides of the preform.

Abstract: An improved method of forming an article includes providing continuous woven, flat, helical tape of filaments and a continuous flat, helical tape of foil. The two helical tapes are interleaved to form a helical assembly having turns of filaments alternating with turns of foil. Deformation forces are applied against the turns of the helical assembly in a direction parallel to the central axis of the helix to bond the turns of the tapes of foil and filament together while maintaining the filaments free of axially extending forces. During the bonding of the turns of the helical foil and filament tapes, the tapes may be bonded to a housing or other component of an article to be reinforced. Radial reinforcing can be provided by including in the helical assembly a layer having filaments with central axes which are radial relative to the central axes of the filaments of the helical tape.

Abstract: A composite article is made by braiding a 3D article shaped preform including non-fugative braider reinforcing fibers and fugative fibers and removing the fugative fibers to form a plurality of matrix-ingress passages in the braided preform. During impregnation of the braided preform with a matrix material, matrix material is supplied to the interior of the preform via the passages. The fugative fibers typically comprise fugative monofilaments which are substantially larger in size than the non-fugative fibers to permit one or more dimensions of the preform and thus the composite article to be increased beyond the capacity of the particular braiding apparatus employed.

Abstract: A transversely twisted hollow airfoil member is provided by diffusion bonding together airfoil components each having a skin or shell in the form of a partial airfoil twisted transversely along its length and one or more internal support ribs having bonding surfaces which are not twisted transversely along their length. Each support rib extends substantially normal to a bonding plane defined by bonding surfaces on the support ribs. As a result of the rib and bonding surface orientation, the airfoil components can be forged and the components bonded together at elevated temperature in short times between dies movable by high pressure toward one another normal to the bonding surfaces.

Abstract: An electrolyte chamber includes a cathode movable in the chamber toward a workpart to machine same and spaced from a wall of the chamber by a transverse clearance space and further includes a sealing piston movable transversely in the chamber in opposite directions toward and away from the cathode to substantially close off or open the clearance space. The sealing piston includes one or more fluid passages extending therethrough such that electrolyte pressure exerted on the sealing piston is substantially balanced in the opposite directions of movement such that unbalanced electrolyte pressure forces do not prevent the sealing piston from closing off the transverse clearance.

Abstract: A method for fabricating long-length and/or large-sized dense filamentary reinforced monotapes. The method comprises forming a layered sandwich of matrix foils or encapsulating sheets plus foils around a reinforcing mat of collimated fibers and sealing the edges of the assembly. The sealing step is carried out with the sandwich formed to a predetermined arcuate configuration such that the sandwich can be coiled after edge sealing without buckling the encapsulating sheets or disturbing the filament alignment and orientation. The formation of the sealed, encapsulated preform can be carried out using continuous processing techniques. Subsequent processing, such as densification, can be performed with the preform in the coiled condition or after it is uncoiled to approximately the arcuate configuration of the sealing step.

Abstract: An electrochemical machine of the type having a workpart shroud around the workpart except for the portion thereof to be received in an electrolyte chamber with the shroud and electrolyte chamber substantially enclosing the workpart during machining is provided with opposing clamps on an electrolyte chamber member to cammingly engage opposite lateral sides of the shroud to hold it against the electrolyte chamber member to reduce high pressure electrolyte leakage.A venting conduit system is provided from the shroud through mated engaged surfaces of the shroud and electrolyte chamber member to an electrolyte drain in the electrolyte chamber to vent gases from the shroud during machining. Flow of high pressure electrolyte through the electrolyte chamber and drain creates a suction on the shroud interior to cause venting of gases, such as hydrogen, therefrom.

Abstract: A workpart to be the anode for electrochemical machining by a cathode tool is disposed on a shaft having a free end. An electrical coupling housing is disposed on the free end for movement thereon between electrical contact and non-contact positions. A stop extends axially from the free end of the shaft on a connector rod. A fluid actuated piston/cylinder assembly is disposed on the connector rod between the electrical coupling housing and stop. When the piston is actuated, it extends to abut the stop and, as a result of the reaction force, causes the cylinder housing to bias the coupling housing in the opposite direction from piston movement to the electrical contact position to effect electrical connection between the coupling housing and free end of the shaft.The workpart shaft includes a peripheral toothed portion driven by a pinion gear to index the shaft and workpart thereon.