STABILITY OF COPPER SEGREGATIONS ON COPPER CARBON METAL-MATRIX COMPOSITE INTERFACES UNDER ALLOYING/

The problem of stability of interfaces in metal-matrix composites is r educed to the investigation of the segregation of copper atoms at the metal/fibre interface. Calculations of excess thermodynamic functions of interstitial solid solutions are performed. The influence of additi ves on the stability of copper segregations formed on the fibres is di scussed. The wettability of the carbon/copper interfaces is regulated by the solubility of the fibre in the matrix with different dopants. I t is shown that alloying of the matrix by the additional element, subs tituting copper in the interstitial metal-metalloid solid solution, ch anges the value of the mixing energy and influences the volume fractio n of two-dimensional segregations of copper. Some additives are predic ted as the best alloying elements for preventing the copper segregatio ns on the composite interfaces. (C) 1997 Elsevier Science Limited.