Fibre impregnated composites - by forming a eutectic alloy in situ over the fibres

摘要

High mechanical strength fibres e.g. graphite, boron, SiC-coated boron carbide, steel, tungsten, silica, SiC or Al2O3, which can be incorporated into light metal matrices, are initially sheathed in component A (e.g. Cu, Ni, Ag, Co, Cu-alloy, opt with C, Si or P) to a uniform thickness with a 50% variation in max. thickness. A second constituent B (e.g. Mg and/or Al) is added, chosen so as to form a eutectic or lower m. pt. alloy with A. The assembly is then heated at a temp. between the alloy m.pt. and m.pt. of A, so that a liquid phase is formed in situ and impregnates the fibres completely, then the assembly is cooled to complete solidification of the matrix, and is finally thermo(chemically) treated to improve certain properties. The method ensures complete and efficient wetting of the fibres.