Hybrid three-dimensional woven/laminated struts for composite structural applications

A method of manufacturing a woven preform used to reinforce a composite structure comprising the steps of:

• weaving a plurality of layers together to form a monolithic central portion;
• weaving a plurality of independent layers to form a first end portion;
• weaving said plurality of independent layers to form a second end portion, wherein plies of said plurality of independent woven layers extends through the entire length of said preform, wherein said plies are integrally woven in said central portion to form a three dimensional fabric construction, and wherein said plies are independently woven in said end portions to form a stack of woven fabric;
• and
• interspersing bias plies between said plurality of independent woven plies in said first and said second end portions.

A three-dimensional composite structure reinforced with a woven preform comprising:

• a central portion having a plurality of interwoven layers;
• a first end portion having a plurality of independent woven layers;
• a second end portion having said plurality of independent woven layers;
• wherein plies of said plurality of independent woven layers extend through the entire length of said preform wherein said plies are integrally woven in said central portion to form a three dimensional fabric construction;
• and
• wherein said plies are independently woven in said end portions to form a stack of woven fabric;
• wherein bias plies are interspersed between said plurality of independent woven layers plies in said first and second end portions;
• and
• a matrix material.

A woven preform used to reinforce a composite structure comprising:

• a column portion having a plurality of interwoven layers;
• and
• a lug end portion having a plurality of independent woven layers, wherein plies of said plurality of independent woven layers extend through the entire length of said preform wherein said plies are integrally woven in said column portion to form a three dimensional fabric construction;
• and
• wherein said plies are independently woven in said end portion to form a stack of woven fabric;
• wherein bias plies are interspersed between said plurality of independent woven layers plies in said lug end portion.

A woven preform for use as reinforcement in a composite structure comprising:

• a three-dimensional central portion having a plurality of warp fibers interwoven with a plurality of weft fibers in three dimensions (X, Y, and Z);
• a first end portion;
• and
• a second end portion;
• wherein said woven preform comprises one or more warp fibers on an outer surface of said preform that extend continuously on the outer surface along the entire length of said woven preform;
• and
• wherein said woven preform comprises one or more warp fibers that extend along the entire length of said woven preform and a plurality of warp fibers that weave out of said woven preform and provide a transition from said central portion to at least one of said first and second end portions.

A method of manufacturing a woven preform for use as reinforcement in a composite structure comprising the steps of:

• weaving a plurality of warp fibers with a plurality of weft fibers in three dimensions (X, Y, and Z) to form a three-dimensional central portion;
• weaving a plurality of the warp fibers with a plurality of weft fibers in three dimensions (X, Y, and Z) to form a three-dimensional first end portion;
• weaving a plurality of the warp fibers with a plurality of weft fibers in three dimensions (X, Y, and Z) to form a three-dimensional second end portion;
• wherein the woven preform comprises one or more warp fibers on an outer surface of said woven preform are woven to extend along the entire length of said woven preform;
• and
• wherein said woven preform comprises one or more warp fibers that extend continuously on outer surface along the entire length of said woven preform and a plurality of warp fibers that weave out of said woven preform and provide a transition from said central portion to at least one of said first and second end portions.

A woven preform for use as reinforcement in a composite structure comprising:

• a three-dimensional central portion having a plurality of warp fibers interwoven with a plurality of weft fibers in three dimensions (X, Y, and Z);
• and
• wherein said woven preform comprises one or more warp fibers on an outer surface of said woven preform that extend continuously on the outer surface along the entire length of said woven preform;
• and
• wherein two or more warp fibers in adjacent layers exchange position through a thickness of the central portion at a bifurcation at an end of said central portion.

A woven preform for use as reinforcement in a composite structure comprising:

• at least one end portion;
• and
• a three-dimensionally woven central portion comprising a plurality of warp fibers interwoven with a plurality of weft fibers in three dimensions (X, Y, and Z) comprising:
• the plurality of weft fibers comprising first yarns extending in a weft direction;
• the plurality of warp fibers comprising second yarns extending in a warp direction, wherein the first and second yarns form interwoven layers in the central portion;
• wherein there is a greater number of second yarns in a first region of the woven central portion than in a second region of the woven central portion.

A woven preform for use as reinforcement in a composite structure comprising:

• at least one end portion;
• and
• a three-dimensionally woven central portion comprising a plurality of warp yarns interwoven with a plurality of weft yarns in three dimensions (X, Y, and Z),
• wherein one or more warp yarns extend along the entire length of said preform, and one or more warp yarns extend less than the entire length of said preform.