Method for making an internal combustion engine piston in thermostructural composite material

A method of making a piston for an internal combustion engine out of thermostructural composite material formed of fiber reinforcement densified by a matrix, the method being characterized in that it comprises the steps consisting in:

• making a fiber structure by superposing plies of fiber fabric and bonding the plies together by needling, so that the fibers of the superposed plies extend essentially in a first direction (X) and in a second direction (Y) orthogonal thereto, the plies being bonded together by fibers that are displaced by the needling in a third direction (Z) that is transverse relative to the plies;
• cutting out a piston preform from the needled fiber structure so that one of the first and second directions (X, Y) is parallel to the piston longitudinal of the preform that corresponds to the cylindrical side surface of the piston;
• densifying the preform at least partially with the material constituting the matrix;
• and
• machining the piston from the densified preform.