The invention relates to a method for manufacturing a box-shaped monolithic structure with a cavity by curing a fiber-reinforced prepreg material. The method comprises using two or more elongated and internally hollow support tools which have a complementary form to that of the cavities to be manufactured, and a composition based on reinforcement material and polymer suitable to allow the passage from a rigid state to a flexible elastomeric state and vice versa in response to heating/cooling down. In the rigid state, the support tools allow the direct lamination of the prepreg material on their external walls and are configured to set the flexible elastomeric state at a temperature lower than the curing temperature and higher than 50° C. During the curing operation, the curing pressure is applied both outside the structure being formed and inside the support tools, whose walls have become flexible, to push on the prepreg material to be cured.

A method of constructing a mandrel generally complementary to a spar cavity of a spar includes connecting a first component and a second component to form a central space there between and inserting a center component within the central space such that the center component retains the first component and second component in a desired position forming an outer surface of the mandrel which corresponds to an inner surface of the spar cavity.

Systems and methods are provided for forming composite parts. One embodiment is an apparatus that includes a forming tool. The forming tool includes a body, which includes an exterior that defines a shape for forming a laminate that will be cured into a composite part. The body also includes elements of phase change material that provide rigidity to the body below a threshold temperature, and that exhibit a phase change above the threshold temperature causing the body to become pliable. Further, the body includes flexible material that encloses the elements of phase change material.

A seal structure is used in a mold constituted by a plurality of segments to manufacture a hollow composite material structure. In the seal structure, a seal member formed in a line shape having ends is inserted in a seal groove provided on at least one of adjacent side surfaces of the segments. A lip portion is provided at a seal upper portion of the seal member such that at least a tip end of the lip portion projects to an outside of the seal groove. When the adjacent side surfaces of the segments are coupled to each other, the seal member is crushed in a cross sectional direction by the other of the adjacent side surfaces of the segments. With this, complication of the manufacture of the composite material structure can be suppressed or avoided while realizing a satisfactory sealed state between the adjacent segments.

A mold for a composite material structure includes: a plurality of segments including side surfaces configured to be coupled to each other, seal grooves being provided on at least one of the adjacent side surfaces; a pair of annular holding members configured to fix both respective end surfaces of the segments to keep them as a single structure; and seal members configured to seal between the segments when the side surfaces are coupled with the seal member inserted in the seal groove. Each seal member is formed in a line shape having ends. A lip portion is provided at a seal upper portion of the member. The seal member is hollow or includes a concave portion on at least a seal bottom portion thereof. With this, complication of manufacture of a hollow composite material structure can be suppressed or avoided while realizing a satisfactory sealed state between the adjacent segments.

Tooling for use in forming a variable taper component is provided. The tooling includes an inner mandrel and an outer mandrel disposed around the inner mandrel. The inner mandrel includes a master insert defining opposed tapered edge faces, an external surface having a variable taper and a plurality of recesses configured to receive at least a portion of the variable taper component, and a tapered internal surface. The inner mandrel also includes a plurality of interlocking pieces arranged concentrically around the master insert, and a tapered inner sleeve disposed against the tapered internal surfaces of the plurality of interlocking pieces and the master insert. The outer mandrel defines a corresponding plurality of recesses configured to receive at least a portion of the variable taper component, wherein a maximum width of the interlocking pieces and the master insert is smaller than a minimum width of ends of the variable taper component.

An additively manufactured mandrel is disclosed, including a plurality of separable segments arranged to form a main body having a first end and a second end, each separable segment connected to adjacent segments. A first plug connected to the first end, and a second plug connected to the second end of the main body are configured to support the main body during a composite curing process.

A product may include a mold assembly comprising a mold inner tube, a mold outer tube, a first end cap, and a second end cap, and an inner texture sleeve; a cured mold product comprising about 20 parts by weight of a dry powder and about 540 parts by weight of water; and at least one sleeve positioned circumferentially around the cured mold product being constructed and arranged to provide constrictive force on the cured mold product.

A substantially air-tight triple seal arrangement along a seam between first and second tool segments comprises inner, middle and outer seals forming first and second substantially air tight vacuum chambers.

The invention relates to a process for producing complex, mould-foamed rigid foam materials, more particularly of poly(meth)acrylimide (P(M)I) cores, preferably of polymethacrylimide (PMI) cores, which may be employed, for example, in carmaking or aircraft construction. A feature of the process is that through use of a particulate core during foam, it is possible to achieve an additional weight saving relative to foam materials or sandwich materials of the prior art.