Hexcel Corporation

Hexcel Corpation

Milton F Custer

Kevin D McVicker

Don C Christensen

Carol J Laufenberg

Kenneth S Baron

Andreas G Hegedus

Thomas K Owen

James R Watts

James D Mercer

Kenneth M Holland

William R Sherwood

W Mark Bielawski

Kenneth E Vicknair

Hoover Larry Ng

Becky A Simpson

George Green

Richard G Kvalheim

Composite prepreg including a gas venting network that allows multi-dimensional escape of gas from the prepreg during the curing process. Penetrable barriers are also provided between the matrix precursor elements to promote long-term storability of the prepreg at ambient temperatures. All or a portion of the gas venting network may be integrated with the penetrable barriers.

Prepreg with integrated multi-dimensional gas venting network

The invention provides a high temperature, damage tolerant candle filter (4) made of a porous ceramic material which is designed so that, if it fails, it does not fail catastrophically. The ceramic candle filter includes a hollow tube (14) having an open end, a closed end and a porous outer wall therebetween. The porous wall is made of a fiber ceramic reinforcement material impregnated with ceramic particles and a fugitive material that is substantially removed from the fiber ceramic reinforcement material or partially converting into a permeable material to provide porosity. The reinforcement material is generally strong enough to absorb the initial explosion force created when the ceramic particle carrier fails during, for example, reverse pressurization of the candle filter, thereby preventing the ceramic pieces from becoming projectiles.

Candle filter and method for making

A heat exchanger tube (2, 2a, 2b) is made using a hollow, impermeable, monolithic ceramic inner tube (4) and wrapping the inner tube with a circumferentially extending reinforcing material (12) impregnated with a slurry of ceramic particles, particle carrier medium and thermoset binder. The combination of the inner tube and the impregnated reinforcing material is first heated to solidify the thermoset binder. The combination is then sintered to drive off the particle carrier medium and themoset binder to create a two-layer heat exchanger tube including the inner tube and an outer tube (6).

Heat exchanger tube and method for making

Ceramic honeycomb (32) is made by applying adhesive (10) to parts of node regions (6) of a stack (12) of ceramic fabrics (2) to bond adjacent fabrics to one another at nodes (20) defined by the adhesive. The ceramic fabric stack is expanded and then impregnated in a ceramic matrix. The impregnated stack (18), dried to be self-supporting but still flexible, can be kiln-fired at this point or it can be encapsulated in an encapsulant (26) such as polyvinyl alcohol. The encapsulated stack (24) is then autoclaved at 100 psi and 185.degree. F. causing the matrix binder to set, thus rigidifying the encapsulated fabric stack. Autoclaving also causes the fabric at the nodes to squeeze together to create intimate contact, and thus high strength bonds during subsequent firing, between the fabrics at the nodes. The encapsulated stack is fired to drive off non-ceramic material to create the ceramic honeycomb. The minimum bending radius of the ceramic fibers at the nodes can be increased using one or more methods.

Method for making ceramic honeycomb

A fiber protective coating system for storing, handling and protecting high modulus fibers is disclosed. An exemplary system includes a plurality of generally elongated and collimated fibers comprising a fiber bundle with fibers mutually bonded by one or more coatings of a resin and formed into a cylindrical configuration of twisted fibers for feeding directly to a loom in order to form a woven fabric.

High modulus reinforcement and dip-coat production method for same

A ceramic heat exchanger tube (1) includes a hollow ceramic outer tube (2) with a corrugated ceramic fiber inner member (8) housed within and secured to the outer tube defining one or more fluid passageways (14) therebetween. The corrugated inner member helps to keep the outer tube from failing catastrophically by momentarily slowing down the initial outwardly expanding movement of the pieces of the failed outer tube. This keeps the pieces of the failed outer tube from being blown outwardly in a shrapnel-like manner to prevent damage to adjoining tubes.

Method of making a continuous ceramic fiber reinforced heat exchanger

Fiber materials of unidirectional, parallel filaments are fully impregnated with highly viscous resins such as polymers having linear, long chain molecular structures, by heat softening the resin, applying it to opposite sides of the fiber material, subjecting it to low pressure (e.g. 4 psi) and generating shear stresses in a boundary layer of the pressurized resin immediately adjacent the faces of the fiber material to align the long chain molecules in the vicinity of the filaments substantially parallel to the filaments. Shear is generated by moving the material, including the applied resin, through a restricted passageway which defines a shear zone. While the resin is subjected to shear its viscosity is reduced to such an extent that it penetrates into the fiber material and substantially fully encapsulates the fibers with the resin.

Method and apparatus for impregnating fibers with highly viscous

A composite pre-slit tape useful as a protective carrier system for storing and handling high modulus fibers and processes for protecting such fibers are disclosed. An exemplary composite pre-slit tape includes a plurality of generally elongated and collimated pre-slit laminates oriented in a single plane and releasably bonded to a removable continuous backing layer which is in the form of a long thin tape. Each pre-slit laminate includes an adhesive layer located adjacent the continuous backing layer and a fiber supporting layer located adjacent the adhesive layer. In use as a fiber protective carrier, each pre-slit laminate is bonded to a fiber bundle of a plurality of collimated fibers arranged in a single layer. Each fiber is bonded along its length to the supporting layer of the pre-slit laminate. The combination of secured fibers and pre-slit laminate can be fed directly to a loom for forming woven fabric.

High modulus fiber protective carrier systems and methods for their use

A glass matrix/ceramic fiber reinforcement composite is prepared from a yarn formed by spinning glass fiber and ceramic fibers lengths together, to form a bicomponent yarn. The yarn is weavable and spinnable, and accordingly may be prepared in fabric forms, or in windings, of predetermined shape. The precursor is melted by heating to the temperature of the melting point of glass, which fused the glass into a continuous matrix, surrounding the ceramic reinforcement.

Ceramic reinforced glass matrix

An orthopedic cast material having a thermoplastic material and provided with a quantity of (poly)ethylene oxide applied thereto to prevent adherence of adjacent convolutions of the cast material when it is in the form of a roll and is immersed in hot water prior to being wrapped on a limb or body part of a patient. The (poly)ethylene oxide can be in the form of a coating on the outer surface of the cast material or in the resin of the cast material.

Separator medium for orthopedic cast material

Orthopedic structures are prepared from a thermal softening resin (e.g. polycaprolactone) impregnated large mesh knit fabric carrier having relatively large diameter strands and having a relatively high weight ratio of the polycaprolactone or equivalent resin composition to the fabric carrier. The impregnated fabric can be formed in rolls which may be warmed above the softening temperature of the resin. The thermally softened impregnated fabric becomes highly flexible and pliant and may then be wrapped in multiple layers about the limb to be immobilized. The large knit fabric carrier allows for twisting of the fabric, forming and reforming, so as to obtain the desired shape and degree of support. The overlapping layers of impregnated fabric bond to each other during wrapping and whereafter the impregnated fabric rapidly cools to a hard structurally stable cast, which is porous so as to minimize maceration or other deleterious skin conditions from developing.

Moldable plastic orthopedic cast

A heat softenable orthopedic bandage assembly which comprises a length of a pliant fabric material to which a heat softenable polymer composition is applied. The fabric material is wound up into a roll and a separator is placed between adjacent fabric convolutions of the roll. The separator is constructed of a material that is readily releasable from the heat softenable composition, it is relatively thin, and includes a multiplicity of apertures which have a size less than the size of the openings in the fabric carrier. The cast is formed by submerging the roll in heated water to heat the temperature of the composition above its softening temperature. While submerged water is flowed in a radial direction past the carrier openings and the separator apertures towards the center of the roll to speed up the softening process. When the roll is removed from the water to form the orthopedic cast the separator prolongs the cool-down time over what it would be if no separator were used to extend the available time during which the cast may be formed.

Method and apparatus for applying heat softenable orthopedic cast

A honeycomb sandwich cast for supporting human or animal body portions. The cast has inner and outer cast layers which, in the finished cast, are rigid, and a central honeycomb core having honeycomb cells which are perpendicular to the skin of the underlying body portion. The honeycomb is securely attached, e.g., mechanically locked or bonded to the cast layers to form an integral, high strength, low weight honeycomb structure. An indentable, resiliently compressible fabric such as reticulated plastic foam may optionally be positioned between the faces of the honeycomb core and the cast layers. With use of such a foam, when the outer layer is applied normally by wrapping a bandage-like fabric about the body portion and the surrounding honeycomb core, a compressive force is generated which presses portions of the foam structure into the honeycomb cell openings to form a more secure interlock and prevent relative movement between the components of the cast. The foam structure can subsequently be rigidified to form a mechanical interlock between it and the honeycomb.

Growing community of inventors

Byron, CA, United States of America

Milton F Custer