Extrusion-based additive manufacturing method and apparatus

摘要

A method of manufacturing an object, whereby a filament (3f) is fed to an extrusion head (4). The filament (3f) 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 (3f) . 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 (4) 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 (3f) melts within the extrusion head (4) , thereby forming a partially molten filament within the extrusion head (4) . The partially molten filament is extruded from the extrusion head ( 4) onto a substrate (5) , the reinforcement portion of the partially molten filament remaining in a semi-crystalline state as it is extruded from the extrusion head (4) . Relative movement is generated between the extrusion head (4) and the substrate (5) as the partially molten filament is extruded onto the substrate (5) in order to form an extruded line on the substrate (5) . The matrix portion of the extruded line solidifies after the extruded line has been formed on the substrate (5) .