Abstract: A method for forming a composite material including reinforcing fibers includes connecting end portions of the reinforcing fibers with equipotential materials to form an electroconductive loop including the reinforcing fibers in the composite material before reaction; and applying a magnetic field in a direction intersecting a plane formed by the electroconductive loop.

Abstract: A joint portion evaluating method for measuring and evaluating a joint state of a joint portion at which a first joint body and a second joint body are joined together, the joint portion evaluating method including the steps of: acquiring as a reference value a capacitance value of the joint portion in a reference measurement state serving as a reference for measurement conditions; changing a measurement state from the reference measurement state and acquiring as a measured value a capacitance value of the joint portion in a changed measurement state arising after the change of the measurement state; deriving as a measurement evaluation value a value obtained by referencing the measured value with the reference value; and performing an evaluation based on the derived measurement evaluation value.

Abstract: A composite material forming device forms a composite material including a resin and reinforced fibers having electrical conductivity. The composite material forming device includes: a conduction jig having electrical conductivity, the conduction jig being to be placed on a surface of the composite material so as to make a bridge between both end portions of the reinforced fibers in a fiber direction; and an electric current generating unit that generates an electric current in the conduction jig. The conduction jig placed on the surface of the composite material and the reinforced fibers form a closed loop through which the electric current flows so that the closed loop intersects the surface of the composite material.

Abstract: A joint structure includes a reinforcement portion that is formed by joining a composite material and a reinforcing material through an adhesive. The composite material includes a plate portion that is formed by laminating a plurality of fiber sheets, and a raised portion that is formed by laminating a plurality of fiber sheets in addition to the plurality of fiber sheets of the plate portion, and surfaces of the plate portion and the raised portion are covered with a single fiber sheet. The reinforcement portion includes the raised portion and the reinforcing material that is bonded to the raised portion through an adhesive. A first boundary between the plate portion and the raised portion and a second boundary between the raised portion and the reinforcing material are located at different positions in an in-plane direction of a laminated interface between the fiber sheets that are laminated.

Abstract: A heating device includes a magnetic field heating coil that inductively heats a composite material by a magnetic field. The composite material has a length in a depth direction and a length in a width direction orthogonal to the depth direction. The magnetic field heating coil has a first coil part provided along the width direction, and a pair of second coil parts provided on both sides of the first coil part in the width direction so as to be continuous with the first coil part, the second coil parts being tilted a predetermined angle ? to one side in the depth direction with respect to the width direction. The first coil part and the second coil parts are symmetric with respect to a line segment drawn in the depth direction at a center of the first coil part in the width direction.

Abstract: A bonding layer evaluation system includes an elastic wave generation device configured to generate an elastic wave at an evaluation object including a bonding layer; an elastic wave detection device configured to detect the elastic wave from the evaluation object; and a control device configured to evaluate a parameter related to the bonding layer of the evaluation object. The control device compares an actual value of a frequency characteristic of the elastic wave detected by the elastic wave detection device and a theoretical value of the frequency characteristic of the elastic wave calculated based on a theoretical model related to the evaluation object and evaluates the parameter related to the bonding layer based on a result of the comparison.

Abstract: A desired shape can be easily realized, and a decrease in strength can be inhibited. A method for producing a composite material includes: an insertion step of inserting an inner member in which a second reinforcing fiber is impregnated with a resin into a space of an outer member that is formed of a woven first reinforcing fiber extending in an undulating manner, the outer member including an opening that is provided at at least one end portion and the space that communicates with the opening; and a composite material forming step of forming a composite material in which the outer member and the inner member are joined to each other by curing the resin of the inner member to join the outer member and the inner member to each other.

Abstract: An adhesive injection method is for injecting an adhesive that bonds an outer plate and a reinforcing member. The reinforcing member has through holes bored through the reinforcing member in a direction intersecting a bonding surface facing the outer plate. The method includes positioning the outer plate and the reinforcing member; disposing a sealing material covering a gap between the outer plate and the reinforcing member; and injecting the adhesive into the through holes in order from one end to the other end of the bonding surface. At the injecting, while the adhesive is injected into the through hole, when the adhesive is recognized through another through hole formed adjacent to the through hole into which the adhesive is being injected, a through hole into which the adhesive is to be injected is shifted from the through hole into which the adhesive is being injected to the other through hole.

Abstract: A composite material includes stacked reinforced fiber substrates and has a thickness-varying part whose thickness in a stacking direction changes from a large thickness to a small thickness. The reinforced fiber substrate that has the drop-off portion and is positioned between a base substrate and a cover substrate in the stacking direction is set as a cut substrate. Stress analysis is performed on the base substrate, the cut substrate, and the cover substrate to calculate an evaluation value concerning stress on the cut substrate. A reinforced fiber substrate in the thickness-varying part is set at the cut substrate, based on the calculated evaluation value.

Abstract: A method for forming a composite material including reinforcing fibers includes connecting end portions of the reinforcing fibers with equipotential materials to form an electroconductive loop including the reinforcing fibers in the composite material before reaction; and applying a magnetic field in a direction intersecting a plane formed by the electroconductive loop.

Abstract: A bonding layer evaluation system includes an elastic wave generation device configured to generate an elastic wave from a sample including a bonding layer; an elastic wave reflection body configured to reflect the elastic wave generated from the sample; a sample installation unit provided between the elastic wave generation device and the elastic wave reflection body; an elastic wave detection device disposed in a direction in which the elastic wave is reflected by the elastic wave reflection body, and configured to detect the reflected elastic wave; and a control device configured to evaluate a parameter related to the bonding layer. The control device evaluates the parameter related to the bonding layer by comparing the actual value of the elastic wave detected by the elastic wave detection device with a theoretical value of the elastic wave calculated based on a theoretical model related to the sample.

Abstract: A crystallinity measurement device includes a Raman spectroscopy unit configured to acquire a Raman spectrum of resin-containing material including crystalline thermoplastic resin; and an analysis unit configured to calculate crystallinity of the crystalline thermoplastic resin based on an intensity of a low-wavenumber spectrum that is a spectrum in a region of less than 600 cm?1, in the Raman spectrum.

Abstract: A heating circuit for joining disposed between members includes a heating wire; and a plurality of projections projecting from the heating wire in a facing direction in which the members face each other. Each length of the plurality of projections in the projecting direction is not less than half a layer thickness of a fused layer obtained by the members being melted.

Abstract: A composite material includes a web portion and a flange portion disposed at an end portion of the web portion. The flange portion is formed from fiber sheets laminated and has a surface on one side in a laminating direction of the flange portion serving as an inner surface to which the end portion of the web portion is connected and a surface on the other side in the laminating direction serving as an outer surface. The inner surface of the flange portion has a tapered surface having a thickness that is reduced from a base portion to which the end portion of the web portion is connected toward a front end portion in the laminating direction. The flange portion includes an outermost surface fiber sheet disposed on the tapered surface, the outermost surface fiber sheet serving as the fiber sheet on an outermost surface that covers the tapered surface.

Abstract: A method for bonding a composite material includes impregnating a first composite material containing reinforcing fibers and a second composite material containing reinforcing fibers with a resin and bonding them together. A plurality of protruding members each including a plurality of protrusions protruding in mutually different directions are placed on a surface of the first composite material, and the second composite material is placed where the protruding members are placed. The protruding members are introduced into the interior of the first composite material and the interior of the second composite material while causing the first composite material and the second composite material to come into contact with each other. The first and second composite material are bonded in a state where the protruding members are introduced therein, by curing the resin with which the first and second composite material are impregnated.

Abstract: A computer-implemented method is for designing a composite material in which reinforcement fiber base materials are laminated. The composite material includes a hole extending in a lamination direction of the reinforcement fiber base materials and a reinforcement part provided around the hole. The method includes calculating a strain value generated in the composite material based on design factors and a predetermined load condition, the design factors including a shape of the hole, a shape of the reinforcement part, and an orientation angle of each of the reinforcement fiber base materials in respective layers of the reinforcement part; and optimizing the design factors based on a genetic algorithm such that the calculated strain value tends to decrease.

Abstract: A bladder bag is a mold for molding inside of a composite material structure. The composite material structure includes a narrow portion formed by narrowing a part of the inside and a space portion formed so as to be adjacent to the narrow portion. The bladder bag includes a bladder bag main body and a cord-like member. The bladder bag main body includes a narrow molding portion for molding the narrow portion of the composite material structure, a space molding portion for molding the space portion of the composite material structure, and an air intake for introducing air. The cord-like member is provided inside the bladder bag main body, passes through the narrow molding portion from the air intake, and is connected to an inner surface of the space molding portion.

Abstract: Provided a composite material forming method capable of easily using a composite material that is formed by causing a resin to react in a state where it is joined to another member; and a composite material. The composite material forming method includes a first material preparation step (magnetic field circuit forming material preparation step S11), a second material preparation step (magnetic field circuit non-forming material preparation step S12), a material assembly step S13, and a first heating step (magnetic field heating step S14). In the first material preparation step, a first material including a first resin is prepared. In the second material preparation step, a second material including a second resin is prepared. In the material assembly step S13, the first material and the second material are assembled to each other.

Abstract: A desired shape can be easily realized, and a decrease in strength can be inhibited. A method for producing a composite material includes: an insertion step of inserting an inner member in which a second reinforcing fiber is impregnated with a resin into a space of an outer member that is formed of a woven first reinforcing fiber extending in an undulating manner, the outer member including an opening that is provided at at least one end portion and the space that communicates with the opening; and a composite material forming step of forming a composite material in which the outer member and the inner member are joined to each other by curing the resin of the inner member to join the outer member and the inner member to each other.

Abstract: A method for molding a composite material includes a conductive wire-shaped material arrangement step and a magnetic field application step. The conductive wire-shaped material arrangement step is a step for arranging, in a pre-reaction composite material including reinforcing fibers, a plurality of conductive wire-shaped materials along a direction intersecting the reinforcing fibers with intervals wider than intervals of the reinforcing fibers in a plane on which the reinforcing fibers are arranged. The magnetic field application step is a step for applying a magnetic field in a direction intersecting the plane on which the reinforcing fibers are arranged.