Method for manufacturing a multi-perforated composite acoustic skin without mechanical piercing

Abstract

A method for manufacturing a multi-perforated acoustic skin out of composite material for an acoustic attenuation structure, the method including forming a fibrous preform including a matrix precursor material, carrying out a heat treatment for transforming the precursor into a matrix so as to obtain a multi-perforated acoustic skin made of composite material including a fibrous reinforcement densified by the matrix, the forming of the fibrous preform including draping fibers on a surface of a mandrel including protuberances, and the mandrel and the protuberances can be each made of a material that melts at a temperature lower than the heat-treatment temperature for transforming the precursor into a matrix in such a way as to eliminate the mandrel and the protuberances during the transforming heat treatment step.

Dependencies are inferred from the claim text.