Thermoforming procedure for fibre-reinforced thermoplastic panel e.g. for vehicle engine cover, uses layer of porous material placed in mold before thermoplastic material

摘要

The procedure, using a mold (1) with a matrix (2) and die (3) mobile between an open position and a closed position to form the molding cavity (5), includes the placing a thermoplastic sheet (4) and a porous material (6) in the mold before thermoforming so (6) covers part of the surface between (4) and (5). Pores in (6) are chosen to stop fibres (11) passing through (6) while covering (6) partially with (4). The procedure, using a mold (1) with a matrix (2) and die (3) mobile between an open position allowing a thermoplastic sheet (4) to be inserted, and a closed position in which the molding cavity (5) is formed, includes placing a layer of a porous material (6) in the mold prior to thermoforming to cover at least part of the contact surface between the thermoplastic sheet and mold cavity. The pores in the sheet are selected so as to prevent the passage of fibres (11) from the sheet through the porous material while covering the porous material at least partially with the thermoplastic. An Independent claim is also included for a structural piece made using the procedure.