摘要:
A fiber preform obtained by conforming panels of fiber texture on a former having a surface that reproduces the shape desired for a surface of the nozzle or the nozzle divergent section that is to be made, and by bonding the panels together via their mutually contacting edges, and consolidated fiber reinforcement is formed by shaping the fiber preform impregnated with a consolidation composition comprising a resin, shaping being performed between the former and a jacket applied against the impregnated fiber preform so as to obtain consolidated fiber reinforcement having a fiber volume percentage of at least 35%, and having a thickness of no more than 5 mm over at least a major fraction of its axial dimension. The densification of the fiber reinforcement is continued by chemical vapor infiltration after pyrolyzing the resin so that once densified a part is obtained that has practically the shape and the wall thickness of the nozzle or the nozzle divergent section that is to be made.
摘要:
A fiber preform is obtained by conforming panels of fiber texture on a former having a surface that reproduces the shape desired for a surface of the nozzle or the nozzle divergent section that is to be made. The panels are bonded together via their mutually contacting edges. A consolidated fiber reinforcement is formed by shaping the fiber preform impregnated with a consolidation composition including a resin. The shaping of the fiber preform is performed between the former and a jacket applied against the impregnated fiber preform so as the consolidated fiber reinforcement has a fiber volume percentage of at least 35%, and a thickness of less than 5 mm over at least a major fraction of its axial dimension. The densification of the fiber reinforcement is continued by chemical vapor infiltration after pyrolyzing the resin so that once densified, a part is obtained that has practically the shape and the wall thickness of the nozzle or the nozzle divergent section that is to be made.
摘要:
The wheel comprises a central portion, or rim provided with blades at its peripheral portion and is made of a single piece of composite material formed by a fibrous reinforcement densified by a matrix. The fibrous reinforcement is formed from a helical fabric with radially oriented fibers and circumferentially oriented fibers. The density of fibers in a radial direction and the density of fibers in a circumferential direction varies along a radius of the wheel as a function of the variations of the radial stresses and circumferential stresses that are exerted on the wheel when it is in operation. At least part of the circumferentially oriented fibers in the rim are made of a material having high mechanical resistance, while at least part of circumferentially oriented fibers in the blades and at least part of the axially oriented fibers are made of a material having good resistance to high temperatures and chemical attacks.