Abstract: The object of the invention is a process for the production of a reinforced acoustically resistive layer, in which there is produced a layer of structural reinforcement from fibers pre-impregnated with a thermosetting or thermoplastic resin, said layer having a given quantity of open surface relative to the acoustic waves to be handled, there is associated with said reinforcing layer a metallic acoustic cloth whose mesh is suitable for the quantity of open surface of said structural layer, and the polymerization or consolidation of said resins under pressure and temperature suitable for the resins used, is carried out, characterized in that there is associated with the impregnation resin for the fibers a component (2a) adapted for macromolecular interpenetration with said resin during the polymerization or consolidation so as to ensure for the reinforcing layer (2) improved mechanical and adhesive properties for the metallic cloth. Application to the production of acoustic panels.

Abstract: A process is described for the production of holes, particularly of micro-perforations, in a composite material, constituted by fibers embedded in a resinous matrix, characterized in that it consists in a preliminary step of carrying out on a specimen of the composite material, with the help of a laser beam, tests consisting in adjusting the duration of illumination at a predetermined place on the specimen, as well as the focusing and power of said laser beam, so as to confine the temperature in the mass of the material to a range of temperatures both greater than the thermal decomposition temperature of the matrix resin and below the temperature of altering the physical properties of the fibers, so as to carry out the elimination of the resin without affecting the physical integrity of the fibers, then in reproducing on the material (8) to be treated, at each position of a perforation to be made, the operating conditions of the laser (10, 12) so as to constitute in said material a through passage, as a resul

Abstract: The object of the invention is a process for the production of holes, particularly of micro-perforations, in a composite material, constituted by fibers embedded in a resinous matrix, characterized in that it consists in a preliminary step of carrying out on a specimen of the composite material, with the help of a laser beam, tests consisting in adjusting the duration of illumination at a predetermined place on the specimen, as well as the focusing and power of said laser beam, so as to confine the temperature in the mass of the material to a range of temperatures both greater than the thermal decomposition temperature of the matrix resin and below the temperature of altering the physical properties of the fibers, so as to carry out the elimination of the resin without affecting the physical integrity of the fibers, then in reproducing on the material (8) to be treated, at each position of a perforation to be made, the operating conditions of the laser (10, 12) so as to constitute in said material a through p

Abstract: The object of the invention is a process for the production of a reinforced acoustically resistive layer, in which there is produced a layer of structural reinforcement (2) from fibers pre-impregnated with a thermosetting or thermoplastic resin, said layer having a given quantity of open surface relative to the acoustic waves to be handled, there is associated with said reinforcing layer (2) a metallic acoustic cloth (5) whose mesh is suitable for the quantity of open surface of said structural layer, and the polymerization or consolidation of said resins under pressure and temperature suitable for the resins used, is carried out, characterized in that there is associated with the impregnation resin for the fibers a component (2a) adapted for macromolecular interpenetration with said resin during the polymerization or consolidation so as to ensure for the reinforcing layer (2) improved mechanical and adhesive properties for the metallic cloth (5).