A method for molding fiber-reinforced plastic. A core is formed in a desired shape by accommodating, in a flexible bag, a grain group containing plurality of grains. The core is placed inside a prepreg containing resin and fibers, and the prepreg, in which the core is housed is placed in a molding die and compression molded. When doing so, the grain group contains first and second grains (a,b) that satisfy the equation (1). (1) 1.1(Da/Db)2.0 In the equation Da is the grain diameter of the grains (a), and Db is the grain diameter of the grain (b). When using a molding die to mold a molded article having a cavity, the above mentioned molding method enables an increase in the internal pressure of the core in order to change the peripheral surface area of the core, without using a pressurized gas and/or pressurized liquid.

A flexible punch and die are used to form a flat composite laminate charge into a stiffener having a desired cross sectional shape. A desired contour is formed in the stiffener by bending the punch and die. Ply wrinkling is avoided during contouring by maintaining those portions of the stiffener subject to wrinkling in tension as the contouring is being performed. Bridging of the plies during the contouring process is avoided by first contouring those sections of the stiffener that are subject to wrinkling, and then contouring the remaining sections of the stiffener.

A molding process and device produce a hybrid composite part. The process includes configuring a mold cavity (102) to receive a prepreg material (116), configuring the mold cavity further to receive an injection of material, and providing a mold core (104) including at least one main core (112). The at least one main core (112) are configured to move with respect to the mold core (104). The process includes moving the mold core (104) with respect to the mold cavity (102) with a first actuator mechanism, moving the mold core to take a first configuration, forming with the mold core in the first configuration a preform from the prepreg material, moving the mold core to take a second configuration, and over molding onto the preform with the injection of the material with the mold core in the second configuration.

An in-tool system for compacting an out-of-plane feature of a composite structure. The in-tool system comprises a cavity formed in a tool, a stiffener preform, and an insert. The cavity has an angled surface. The stiffener preform includes an out-of-plane feature, where the out-of-plane feature has a compaction surface. The insert comprises a first face complementary to the angled surface of the cavity and a second face complementary to the compaction surface of the out-of-plane feature. The first face is opposite the second face.

A press molding apparatus includes two dies and press-molds a heated stampable sheet into a predetermined shape by using the two dies. The press molding apparatus includes a movable core provided in at least one of the two dies. The movable core is disposed at an inward side of an edge portion of a cavity. When receiving a pressure greater than or equal to a predetermined value, the movable core moves in such a direction that the cavity increases in volume.

A compacting and injection mold for a fiber preform is for use in fabricating a turbine engine guide vane out of composite material. The mold includes a shell forming a trough that is to receive the fiber preform and that is closed in leaktight manner by bottom and top covers, compacting blocks arranged inside the trough each having a surface pressing normally against a surface of the fiber preform that is to be compacted, and closure blocks arranged inside the trough. Each closure block has a surface pressing normally against a surface of a compacting block and does not have a surface in contact with the fiber preform.

A manufacturing method of a composite structure includes: (a) preparing: a metallic sheet(s) having a through-hole(s) penetrating throughout the metallic sheet(s) in its thickness direction; (b) setting a prepreg(s), constituting a fiber reinforced plastic sheet(s), and the metallic sheet in a pair of dies, which have a recess(es) arranged at a position(s) opposed to one side opening(s) of the through-hole(s), the recess(es) having a larger diameter than the one side opening; (c) closing the dies, wherein, upon closing, (ca) the prepreg(s) and the metallic sheet are molded to the predetermined shape, while surface-contacting therebetween, (cb) at least one of the prepreg(s) and a patch member(s) is extruded into the through-hole(s), so that the shaft part is molded, and (cc) the patch member(s) forms at least part of a head part(s) in the recess(es), the head part(s) integrated with the shaft part(s) and engaging on the metallic sheet(s).

A first cut and kitted material is held against a first flange face of a first die. A second cut and kitted material is held against a second flange face of a second die. The method simultaneously forms the first cut and kitted material against a first blade face of the first die and the second cut and kitted material against a second blade face of the second die. The first cut and kitted material and the second cut and kitted material are clamped between the first die and the second die after forming the first cut and kitted material and the second cut and kitted material. A composite stringer preform comprising the first cut and kitted material, the second cut and kitted material, a noodle, and a base material is cured while the composite stringer preform is against the first forming surface and the second forming surface.

A tool is configured to form a composite charge into a stringer having a net shape with at least one out-of-place feature. The out-of-plane feature is formed by a shim removably attached to the tool. A family of the shims may be used to form a range of out-of-plane features having varying characteristics.

Composite laminate stiffeners such as stringers are punch formed between first and second universal dies respectively carried on first and second trays. The second tray is mounted for sliding movement relative to the first tray between a punch position and a compaction position. Parts of the first and second dies are easily reconfigurable, allowing different shapes of stiffeners to be formed on the same forming apparatus.