Abstract: A method manufacturing a one-piece bowl of thermostructural composite material comprising fiber reinforcement densified by a matrix. The method comprises supplying deformable fiber plies that are whole, being free from slots or cutouts, superposing said plies on a former of shape corresponding to the bowl to be made, deforming the plies, and bonding the superposed plies to one another by means of fibers extending transversely relative to the plies, e.g. by needling so as to obtain a bowl preform which is then densified. The bowl (1) can be used as a support for a crucible (5) in an installation for producing monocrystalline silicon.

Abstract: A one-piece bowl of thermostructural composite material comprising fiber reinforcement densified by a matrix. The bowl is made by supplying deformable fiber in plies that are whole, being free from slots or cutouts, superposing said plies on a former of shape corresponding to the bowl to be made, deforming the plies, and bonding the superposed plies to one another by means of fibers extending transversely relative to the plies, e.g. by needling so as to obtain a bowl preform which is then densified. The bowl can be used as a support for a crucible in an installation for producing monocrystalline silicon.

Abstract: A composite material bowl 36 comprising fiber reinforcement densified by a matrix is made by winding a yarn on a preform 28 having an axial passage 30 through its bottom, densifying the preform by chemical vapor infiltration, and closing the passage by a plug 34. Prior to densification, the preform can be consolidated. A final chemical vapor infiltration step can be performed after the plug has been put into place.

Abstract: Prior to housing the crucible in the bowl, a consumable buffer ply is applied over at least a portion of the inside face of the bowl, the ply being constituted essentially by a non-rigid carbon fiber fabric for protecting the bowl from both physical and chemical interactions with the crucible. The buffer ply is essentially constituted by a flexible fabric selected from: a woven cloth, a knit, a multidirectional sheet, and a thin felt. Prior to putting the ply into place in the bowl, it is possible to form a thin deposit of pyrolytic carbon on the fibers of the fabric.

Abstract: Prior to housing the crucible in the bowl, a consumable buffer ply is applied over at least a portion of the inside face of the bowl, the ply being constituted essentially by a non-rigid carbon fiber fabric for protecting the bowl from both physical and chemical interactions with the crucible. The buffer ply is essentially constituted by a flexible fabric selected from: a woven cloth, a knit, a multidirectional sheet, and a thin felt. Prior to putting the ply into place in the bowl, it is possible to form a thin deposit of pyrolytic carbon on the fibers of the fabric.

Abstract: A friction element is made out of a composite material comprising carbon fiber reinforcement and a matrix which, at least in the vicinity of the or each friction face, comprises: a first phase in the vicinity of the reinforcing fibers and containing pyrolytic carbon obtained by chemical vapor infiltration; a refractory second phase of carbon or ceramic obtained at least in part by pyrolysis of a liquid precursor; and a silicon carbide phase obtained by siliciding, for example. At least in the vicinity of the or each friction face, the composite material is preferably constituted, by volume, at least as follows: 15% to 35% carbon fibers; 10% to 55% first matrix phase containing pyrolytic carbon; 2% to 30% second matrix phase of refractory material; and 10% to 35% silicon carbide. The invention is applicable in particular to braking for rail or road vehicles.

Abstract: A method of manufacturing a honeycomb structure of thermostructural composite material comprising a fiber reinforcing fabric densified by a matrix, the fibers of the reinforcing fabric being of a material selected from carbon and ceramics, as is the matrix, the method comprising the following steps:making a three-dimensional fiber fabric by means of superposed two-dimensional plies that are bonded together by means of fibers passing through the plies;making slit-shaped cuts in a staggered configuration through the plies, and through the entire thickness of the fabric;stretching the cut fabric in a direction that is not parallel to the cuts but that is parallel to the plies so as to form cells whose walls are constituted by the lips of the cuts; andwhile the cut texture is held in the stretched state, densifying it using the matrix-constituting material to obtain a rigid honeycomb structure of thermostructural material.

Abstract: A method of manufacturing a honeycomb structure of thermostructural composite material comprising a fiber reinforcing fabric densified by a matrix, the fibers of the reinforcing fabric being of a material selected from carbon and ceramics, as is the matrix, the method comprising the following steps:making a three-dimensional fiber fabric by means of superposed two-dimensional plies that are bonded together by means of fibers passing through the plies;making slit-shaped cuts in a staggered configuration through the plies, and through the entire thickness of the fabric;stretching the cut fabric in a direction that is not parallel to the cuts but that is parallel to the plies so as to form cells whose walls are constituted by the lips of the cuts; andwhile the cut texture is held in the stretched state, densifying it using the matrix-constituting material to obtain a rigid honeycomb structure of thermostructural material.

Abstract: The wheel (10), which is made from a composite material having a ceramic matrix comprises a hub that bears a drive gear (16) formed of teeth (20) that extend radially on one of the wheel's surfaces (10a). Each tooth is asymmetrical with respect to the meridian plane (21) that passes through its apex, and has first shoulder (20b) that subtends an angle a, preferably between 15.degree. and 45.degree., relative to that plane, and a second shoulder (20c) that subtends an angle b, preferably between 55.degree. and 85.degree., relative to that plane. Advantageously, the sum of the two angels is at least equal to 100.degree.. The turbine wheel has an improved resistance against inter-laminar shear stresses that result from tightening to a drive gear wheel.