Preparation of Semifinished Composite Materials Aluminum–Carbon Fibers

Features of forming semifinished composite materials with a metal matrix reinforced with carbon fibers are considered. The main conditions for preparing these materials and possible technologies based on small diameters of carbon fibers and short distances between them in a beam of the order of several microns are discussed. The conclusion is made that special coatings in the form of silicon carbide and nickel on carbon fibers are needed to improve their impregnation with an aluminum matrix. The chemical deposition of nickel from a bath containing nickel chloride hexahydride, ammonium chloride, sodium hypophosphate, sodium citrate, and lead sulfide is studied. All individual fibers are covered with nickel, and this does not lead to a decrease in their strength. The use of the plasma technology for depositing an aluminum matrix on carbon fibers coated with silicon carbide and nickel is substantiated. The action of the plasma jet does not reduce the strength of the LU-2 carbon tape coated with silicon carbide. However, when aluminum is deposited on the tape with a nickel coating, softening is observed at distances of 50 and 100 mm from the plasma torch. The optimum conditions for the preservation of the strength of carbon fibers during plasma deposition of aluminum on the tapes coated with silicon carbide and nickel are determined by mechanical tests and metallographic studies.