A preform-charge fixture creates a preform charge, which is a partially consolidated assemblage of preforms that can be efficiently transferred to a mold to create a finished part in a molding process, such as compression molding. In the illustrative embodiment, the preform-charge fixture includes peripheral cleats that are movable towards a central cleat to create a small gap therebetween that receives and constrains preforms in a desired position. The fixture also includes clamps, which are operable to engage an uppermost layer of preforms in the gap and apply a slight amount of downward pressure thereto to assure that the preforms are properly seated. The fixture also accommodates an energy source that heats the preforms so that, in conjunction with downforce applied by the clamps and/or gravity, the preforms can be tacked together, forming the preform charge.

A welding method includes: moving a welding head toward a plurality of workpieces, wherein each of the plurality of workpieces includes a polymeric composite, the polymeric composite includes a polymer matrix and a plurality of fibers, and each of the fibers includes a magnetic material; applying a joining pressure to the workpieces with the welding head; applying energy to the plurality of workpieces to melt an interface between the plurality of workpieces, wherein a weld plane is defined at the interface between the plurality of workpieces; and applying a magnetic field to the plurality of workpieces to change an orientation of the plurality of fibers relative to the polymer matrix in the weld area so that the fibers in a weld area are at an angle relative to the weld plane.

A welding method includes: moving a welding head toward a plurality of workpieces, wherein each of the plurality of workpieces includes a polymeric composite, the polymeric composite includes a polymer matrix and a plurality of fibers, and each of the fibers includes a magnetic material; applying a joining pressure to the workpieces with the welding head; applying energy to the plurality of workpieces to melt an interface between the plurality of workpieces, wherein a weld plane is defined at the interface between the plurality of workpieces; and applying a magnetic field to the plurality of workpieces to change an orientation of the plurality of fibers relative to the polymer matrix in the weld area so that the fibers in a weld area are at an angle relative to the weld plane.

A golf club head includes a striking face, a crown and a sole. The crown and/or the sole includes an FRP member formed by a fiber reinforced plastic that contains a fiber and a matrix resin. The FRP member has an average flexural modulus of greater than or equal to 25 GPa. The fiber may contain a carbon fiber. The carbon fiber may have a tensile elastic modulus of greater than or equal to 300 GPa. The fiber may contain a metallic fiber. The FRP member may have a resin content of less than or equal to 40% by weight. The matrix resin may have a glass transition temperature of higher than or equal to 150 C.

A welding method includes: moving a welding head toward a plurality of workpieces, wherein each of the plurality of workpieces includes a polymeric composite, the polymeric composite includes a polymer matrix and a plurality of fibers, and each of the fibers includes a magnetic material; applying a joining pressure to the workpieces with the welding head; applying energy to the plurality of workpieces to melt an interface between the plurality of workpieces, wherein a weld plane is defined at the interface between the plurality of workpieces; and applying a magnetic field to the plurality of workpieces to change an orientation of the plurality of fibers relative to the polymer matrix in the weld area so that the fibers in a weld area are at an angle relative to the weld plane.

A welding method includes: moving a welding head toward a plurality of workpieces, wherein each of the plurality of workpieces includes a polymeric composite, the polymeric composite includes a polymer matrix and a plurality of fibers, and each of the fibers includes a magnetic material; applying a joining pressure to the workpieces with the welding head; applying energy to the plurality of workpieces to melt an interface between the plurality of workpieces, wherein a weld plane is defined at the interface between the plurality of workpieces; and applying a magnetic field to the plurality of workpieces to change an orientation of the plurality of fibers relative to the polymer matrix in the weld area so that the fibers in a weld area are at an angle relative to the weld plane.

Composite fabrication system and associated methods. In one embodiment, a composite fabrication system comprises a molding tool that includes a forming surface at least partially disposed within a constrained space, and a foamable material that expands inside of the constrained space to form an expanded material that presses a layup of one or more composite layers against the molding tool. The composite fabrication system further comprises a curing device configured to cure the layup to form a composite part, and a cutting wire embedded in the constrained space that is heated and configured to cut the expanded material into pieces that are removable from the constrained space.

Composite fabrication system and associated methods. In one embodiment, a composite fabrication system comprises a molding tool that includes a forming surface at least partially disposed within a constrained space, and a foamable material that expands inside of the constrained space to form an expanded material that presses a layup of one or more composite layers against the molding tool. The composite fabrication system further comprises a curing device configured to cure the layup to form a composite part, and a cutting wire embedded in the constrained space that is heated and configured to cut the expanded material into pieces that are removable from the constrained space.

A golf club head includes a striking face, a crown and a sole. The crown and/or the sole includes an FRP member formed by a fiber reinforced plastic that contains a fiber and a matrix resin. The FRP member has an average flexural modulus of greater than or equal to 25 GPa. The fiber may contain a carbon fiber. The carbon fiber may have a tensile elastic modulus of greater than or equal to 300 GPa. The fiber may contain a metallic fiber. The FRP member may have a resin content of less than or equal to 40% by weight. The matrix resin may have a glass transition temperature of higher than or equal to 150 C.

A preform-charge fixture creates a preform charge, which is a partially consolidated assemblage of preforms that can be efficiently transferred to a mold to create a finished part in a molding process, such as compression molding. In the illustrative embodiment, the preform-charge fixture includes peripheral cleats that are movable towards a central cleat to create a small gap therebetween that receives and constrains preforms in a desired position. The fixture also includes clamps, which are operable to engage an uppermost layer of preforms in the gap and apply a slight amount of downward pressure thereto to assure that the preforms are properly seated. The fixture also accommodates an energy source that heats the preforms so that, in conjunction with downforce applied by the clamps and/or gravity, the preforms can be tacked together, forming the preform charge.