Composites Preforms
“Fibrous preform structures are suitable for subsequent processing in which a binding matrix is deposited within the preform structure, thus forming a composite structure. The fibrous preform structures may be suitable for subsequent processing into carbon/carbon structures such as aircraft brake disks. Subsequent processing traditionally involves pyrolyzing the preform structure (if it is formed from a precursor material), and depositing a binding carbon matrix. Depositing the carbon matrix within the preform structure may be accomplished according to known techniques such as chemical vapor infiltration and chemical vapor deposition (CVI/CVD), or by repeatedly impregnating the substrate with a carbon bearing pitch or resin which is subsequently charred, or by any equivalent process.” [Wall, Fiala and Delanoy, US Patent 8,060,997 (11/22/2011)]
Recent US Patents
11/22/2011
8,060,997
Low z preform
Wall, Fiala and Delanoy of Goodrich, North Carolina, developed a fibrous three dimensional structure with a first fibrous layer aligned in the machine direction and an additional fibrous layer at an acute angle to the machine direction. The layers are needled together at a needle density of greater than 55 needle punches per square centimeter. This mat is combined with other fibrous mats and needled at a needle density of less than 60 needle punches per square centimeter, forming a fibrous three dimensional structure. (RDC 11/28/2011)