Patent ID: 6051313
Filing Date: 2000-04-18
Classification: C04B,D02G,F16D,Y10T

Abstract:
A yarn for fabricating fiber preforms for composite material parts, the yarn comprising discontinuous parallel fibers which are not twisted and which are held together by a covering yarn of sacrificial material wound around the fibers, characterized in that the yarn is a hybrid yarn in which the fibers comprise an intimate mixture of fibers of at least two different natures selected from pre-oxidized polyacrylonitrile based carbon fibers or carbon precursor fibers, anisotropic pitch based carbon fibers or carbon precursor fibers, isotropic pitch based carbon fibers or carbon precursor fibers, phenolic based carbon fibers or carbon precursor fibers, cellulosic based carbon fibers or carbon precursor fibers, and ceramic fibers or ceramic precursor fibers, and in that the mixture of fibers comprises carbon fibers or carbon precursor fibers which, in the carbon state, comprise at least 15% by weight of the mixture of fibers and constitute high strength carbon fibers having a tensile strength of at least 1500 MPa and a modulus of at least 150 GPa.