ELECTROLESS METALLIZATION OF CARBON FIBRES FOR PREPARATION OF MMC COMPOSITE

The investigation of the electroless metallization of carbon fiber was presented in this work and namely from different types of Ni-P deposition bath. Deposition of Ni-P barrier layer on carbon fiber surface is one of the means to prevent from harmful Al4C3 formation in MMC composites processing with alumina alloy matrix. In the first step of work the choice of proper bath composition and other parameters of Ni-P deposition for standard ceramic substrates was realized. The proposed glycine-and citric acid-buffered baths allowed for substrate metallization with wide range of deposition rate and coating composition. In the second step of the work the different methods of carbon fiber (Toray T300C i Tenax 5631 HTA) surface pretreatment, before Ni-P metallization, was tested: heat treatment (500, 700 degrees C), cleaning in solvents (acetone, toluene) and solutions of HNO3, H2O2, NaOH, with final conventional SnCl2/PdCl2 activation. The metallization process of such prepared and activated carbon fiber was then characterized in electroless process by Ni-P deposition rate, P-content and coating morphology. The obtained results of investigation created prerequisites for further optimization of process parameters in electroless Ni-P metallization technology of carbon fiber (surface preparation of fibers, deposition of Ni-P).