Abstract:
A method of quality assurance of an additive manufacturing build process. An additive manufacturing system is operated to perform a build process by building a part on a build platform, the part being built by forming a series of layers of metallic material on the build platform. The metallic material melts and solidifies during the build process thereby bonding the part to the build platform and creating thermally induced stress in the part which tends to distort the build platform. During the build process, a parameter is measured which is related to the thermally induced stress in the part to generate measurement data. The measurement data is stored and analysed to determine whether a defect has formed during the build process. A warning is generated if the analysis of the stored measurement data concludes that a defect has formed during the build process. The warning includes an indication of a position in the part.
Abstract:
A method of joining a first component to a second component. A membrane is provided between the first component and a fluid. Pressure of the fluid is used to apply a compression force to a first part of the first component via the membrane. The pressure of the fluid is also used to apply an insertion force to the second component which pushes projections of the second component into a second part of the first component. The method can be integrated into a conventional manufacturing method, such as a “vacuum-bagging” process, which employs fluid pressure and a non-permeable membrane to compress the first component. The pressure of the fluid is used not only to apply the compression force, but also to apply the insertion force to the second component.
Abstract:
A first aspect of the invention provides a method of joining a part to a composite component, the composite component comprising fibres impregnated with a matrix material, and the part comprising a plurality of projections, the method comprising: inserting the projections into the composite component; and pre-heating the projections before they are inserted into the composite component, so that the projections are at a higher temperature than the composite component as they are inserted into the composite component. The projections locally heat the matrix material of the composite component as they are pushed into the composite component. Increased temperature during insertion is advantageous as the reduced matrix viscosity, due to the increased temperature of the matrix, results in better consolidation of the fibres around the projections and minimises the distortion of the fibres. The composite component is only heated locally where heating is required, which removes the need to heat the entire composite component.
Abstract:
A composite assembly with a laminate of fibre plies impregnated with a laminate matrix material is disclosed having pad of fibre plies impregnated with a pad matrix material, and a part with a body with protrusions which extend from the body and penetrate at least some of the fibre plies of the pad. The pad is bonded to the laminate by a stepped lap joint or a scarf joint. The assembly is manufactured by pressing the protrusions into the pad, and after the protrusions have been pressed into the pad, curing a pad matrix material impregnating the pad, and bonding the pad to the laminate.
Abstract:
A filament is fed to an extrusion head. The filament has a semi-crystalline polymeric reinforcement portion and a polymeric matrix portion. The reinforcement and matrix portions run continuously along a length of the filament. The reinforcement portion has a higher melting point and a higher crystallinity than the matrix portion. The temperature of the filament is raised in the extrusion head above the melting point of the matrix portion but below the melting point of the reinforcement portion so that the matrix portion of the filament melts within the extrusion head, thereby forming a partially molten filament within the extrusion head. The partially molten filament is extruded from the extrusion head onto a substrate, the reinforcement portion of the partially molten filament remaining in a semi-crystalline state as it is extruded from the extrusion head. Relative movement is generated between the extrusion head and the substrate as the partially molten filament is extruded onto the substrate in order to form an extruded line on the substrate. The matrix portion of the extruded line solidifies after the extruded line has been formed on the substrate.
Abstract:
A method of additive manufacturing and heat treatment. A substrate is secured to a fixture and an additive manufacturing system is operated to perform a build process by building a part on the substrate secured to the fixture, the part being built by forming a series of layers of metallic material on the substrate, the metallic material melting and solidifying during the build process thereby bonding the part to the substrate and creating thermally induced stress in the part. The part, the substrate and the fixture are moved together from the additive manufacturing system to a heat treatment system, wherein the substrate remains secured to the fixture and the part remains bonded to the substrate as they are moved. The heat treatment system is operated to perform a heat treatment process by heating the part, the substrate and the fixture together thereby relieving the thermally induced stress in the part, the substrate remaining secured to the fixture during the heat treatment process. Finally the substrate is released from the fixture and the part and the substrate are removed from the fixture. The part remains bonded to the support as they are removed from the fixture.
Abstract:
A method of manufacturing an object. A thermoplastic matrix material is melted to transform it into liquid matrix material. The liquid matrix material is fed into a chamber via one or more matrix inlets. A fibre is also fed into the chamber via a fibre inlet. The fibre in the chamber is contacted by the liquid matrix material. A coated fibre is extruded from an extrusion outlet of the chamber onto a substrate, the coated fibre comprising the fibre with a coating of the liquid matrix material, the substrate comprising a previously extruded coated fibre. The fibre moves in and out of the chamber at the same velocity relative to the chamber. The coating fuses with the previously extruded coated fibre and solidifies after it has fused with the previously extruded coated fibre. Relative movement is generated between the extrusion outlet and the substrate as the coated fibre is extruded from the extrusion outlet.
Abstract:
A pressure vessel has a plurality of interconnected hollow spheroids. Each hollow spheroid is truncated to form at least two ports which are fluidly connected to respective ports of adjacent hollow spheroids. Adjacent hollow spheroids have overlapping radii at the connected ports.