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A shaped composite material for braking applications can be produced by a method comprising the steps of: a) providing a mixture comprising bundles of filaments constituted substantially by carbon and having lengths no greater than 30 mm and an organic binder in a mould of the said shape and, at the

A shaped composite material for braking applications can be produced by a method comprising the steps of: a) providing a mixture comprising bundles of filaments constituted substantially by carbon and having lengths no greater than 30 mm and an organic binder in a mould of the said shape and, at the same time, incorporating in the mixture a plurality of reinforcing fibres which extend along the shape in a manner such as to prevent the propagation of cracks, b) forming the mixture comprising the reinforcing fibres to produce a semi-finished product, c) subjecting the semi-finished product to a first firing at a temperature such as substantially to bring about pyrolysis of the organic binder and to a second firing in the presence of silicon.

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The invention claimed is: 1. A shaped composite material formed by a process comprising the steps of: a) mixing a predetermined quantity of bundles of filaments constituted substantially by carbon and having lengths no greater than 30 mm with a predetermined quantity of an organic binder to give a

The invention claimed is: 1. A shaped composite material formed by a process comprising the steps of: a) mixing a predetermined quantity of bundles of filaments constituted substantially by carbon and having lengths no greater than 30 mm with a predetermined quantity of an organic binder to give a mixture, b) placing the mixture in a mould of the said shape and simultaneously incorporating in the mixture a plurality of reinforcing fibres which extend along the shape in a manner such as to prevent the propagation of cracks, c) forming the mixture including the reinforcing fibres as recited in step b) to produce a semi-finished product, d) subjecting the semi-finished product to a first firing at a temperature such as substantially to bring about carbonization or pyrolysis of the organic binder, e) subjecting the fired, semi-finished product to a second firing in the presence of silicon at a temperature such as substantially to bring about fusion of the silicon and infiltration thereof into pores of the semi-finished product to produce the shaped composite material. 2. The shaped composite material according to claim 1, in which the incorporation of the plurality of reinforcing fibres in the mixture comprises the steps of: i) arranging a first layer of the mixture along the shape of the mould, and ii) adding, onto the first layer of the mixture, the plurality of reinforcing fibres which extend along the shape in a manner such as to prevent the propagation of cracks. 3. The shaped composite material according to claim 2, in which the incorporation of the plurality of reinforcing fibres in the mixture comprises the step of: iii) arranging a second layer of the mixture on the first layer so as to cover the plurality of reinforcing fibres completely. 4. The shaped composite material according to claim 1, in which the plurality of reinforcing fibres is incorporated in the mixture in the form of a plurality of bundles arranged in predefined directions. 5. The shaped composite material according to claim 4, in which the predefined directions are warp and weft directions, and in which the bundles form a fabric. 6. The shaped composite material according to claim 1, in which the plurality of reinforcing fibres is incorporated in the mixture in the form of a non-woven fabric. 7. The shaped composite material according to claim 1, in which the organic binder is a dry powder organic binder. 8. The shaped composite material according to claim 1, in which the reinforcing fibres extend along the entire shape of the mould. 9. The shaped composite material according to claim 1, in which the reinforcing fibres are incorporated as an annular portion in the mixture. 10. The shaped composite material according to claim 1, in which the bundles of filaments are randomly arranged in the mixture. 11. The shaped composite material according to claim 1, in which the bundles of filaments and/or the reinforcing fibres are coated with a resin. 12. The shaped composite material according to claim 11, in which the resin is constituted by polyurethane resin. 13. The shaped composite material according to claim 1, in which the quantity of bundles of filaments in the mixture is within the range of 50-80% by volume, relative to the volume of the mixture. 14. The shaped composite material according to claim 1, in which the quantity of organic binder in the mixture is within the range of 5-30% by volume, relative to the volume of the mixture. 15. The shaped composite material according to claim 1, in which the mixture further comprises from 0.7% to 23% by volume, relative to the volume of the mixture, of additives selected from the group comprising graphite, silicon carbide, and metal carbides and nitrides, in powder form. 16. The shaped composite material according to claim 1, in which the reinforcing fibres are selected from the group comprising carbon fibres and metal fibres. 17. The shaped composite material according to claim 16, in which the quantity of reinforcing fibres incorporated in the mixture is within the range of 10-30% by volume, relative to the volume of the material. 18. The shaped composite material according to claim 1, in which the forming step is performed at a temperature of 80-180° C. with the application of a pressure of 0.1-5 N/cm<2> to the mixture comprising the reinforcing fibres. 19. The shaped composite material according to claim 1, in which the first firing of the semi-finished product is performed at a temperature of 900-1200° C., in the presence of an inert gas. 20. The shaped composite material according to claim 1, in which the second firing of the semi-finished product is performed in the presence of an inert gas, at a temperature of 1400-1700° C. and under partial vacuum with a reduced pressure of from 300 to 900 mbars. 21. The shaped composite material according to claim 1, further comprising a step for dry finishing of the semi-finished product, performed after the first firing of step d) and before the second firing of step e). 22. The method according to claim 1, further comprising a step for dry or wet finishing of the semi-finished product, performed after the second firing of step e). 23. A shaped composite material formed by a process comprising the steps of: a) mixing bundles of filaments constituted substantially by carbon and having lengths no greater than 30 mm with a quantity of an organic binder to give a mixture, b) placing the mixture in a mould of the said shape and simultaneously incorporating in the mixture a plurality of reinforcing fibres which extend along the shape in a manner such as to prevent the propagation of cracks, c) forming the mixture including the reinforcing fibres as recited in step b) to produce a semi-finished product, d) subjecting the semi-finished product to a first firing at a temperature such as substantially to bring about carbonization or pyrolysis of the organic binder, e) subjecting the fired, semi-finished product to a second firing in the presence of silicon at a temperature such as substantially to bring about fusion of the silicon and infiltration thereof into pores of the semi-finished product to produce the shaped composite material. 24. The shaped composite material according to claim 23, in which the incorporation of the plurality of reinforcing fibres in the mixture comprises the steps of: i) arranging a first layer of the mixture along the shape of the mould, and ii) adding, onto the first layer of the mixture, the plurality of reinforcing fibres which extend along the shape in a manner such as to prevent the propagation of cracks. 25. The shaped composite material according to claim 24, in which the incorporation of the plurality of reinforcing fibres in the mixture comprises the step of: iii) arranging a second layer of the mixture on the first layer so as to cover the plurality of reinforcing fibres completely. 26. The shaped composite material according to claim 23, in which the plurality of reinforcing fibres is incorporated in the mixture in the form of a plurality of bundles arranged in predefined directions. 27. The shaped composite material according to claim 26, in which the predefined directions are warp and weft directions, and in which the bundles form a fabric. 28. The shaped composite material according to claim 23, in which the plurality of reinforcing fibres is incorporated in the mixture in the form of a non-woven fabric. 29. The shaped composite material according to claim 23, in which the organic binder is a dry powder organic binder. 30. The shaped composite material according to claim 23, in which the reinforcing fibres extend along the entire shape of the mould. 31. The shaped composite material according to claim 23, in which the reinforcing fibres are incorporated as an annular portion in the mixture. 32. The shaped composite material according to claim 23, in which the bundles of filaments are randomly arranged in the mixture. 33. The shaped composite material according to claim 23, in which the bundles of filaments and/or the reinforcing fibres are coated with a resin. 34. The shaped composite material according to claim 33, in which the resin is constituted by polyurethane resin. 35. The shaped composite material according to claim 23, in which the quantity of bundles of filaments in the mixture is within the range of 50-80% by volume, relative to the volume of the mixture. 36. The shaped composite material according to claim 23, in which the quantity of organic binder in the mixture is within the range of 5-30% by volume, relative to the volume of the mixture. 37. The shaped composite material according to claim 23, in which the mixture further comprises from 0.7% to 23% by volume, relative to the volume of the mixture, of additives selected from the group comprising graphite, silicon carbide, and metal carbides and nitrides, in powder form. 38. The shaped composite material according to claim 23, in which the reinforcing fibres are selected from the group comprising carbon fibres and metal fibres. 39. The shaped composite material according to claim 38, in which the quantity of reinforcing fibres incorporated in the mixture is within the range of 10-30% by volume, relative to the volume of the material. 40. The shaped composite material according to claim 23 in which the forming step is performed at a temperature of 80-180° C. with the application of a pressure of 0.1-5 N/cm<2> to the mixture comprising the reinforcing fibres. 41. The shaped composite material according to claim 23, in which the first firing of the semi-finished product is performed at a temperature of 900-1200° C., in the presence of an inert gas. 42. The shaped composite material according to claim 23, in which the second firing of the semi-finished product is performed in the presence of an inert gas, at a temperature of 1400-1700° C. and under partial vacuum with a reduced pressure of from 300to 900 mbars. 43. The shaped composite material according to claim 23, further comprising a step for dry finishing of the semi-finished product, performed after the first firing of step d) and before the second firing of step e). 44. The method according to claim 23, further comprising a step for dry or wet finishing of the semi-finished product, performed after the second firing of step e).