OPTIMIZATION OF THE SURFACE FREE-ENERGY OF CARBON-FIBER THROUGH ELECTROLYTIC OXIDATION

Fiber surface treatments are a method of improving fiber/matrix adhesi on in composite materials, In this study, an electrolytic oxidation pr ocess was systematically optimized as a means of altering the interfac ial region, A statistical experimental design was utilized to examine the effect of process variables on the surface energy of the carbon fi bers, Using a Dynamic Contact Angle Analyzer, in conjunction with the Wilhelmy Plate Technique, the surface energy of each oxidatively treat ed fiber was determined. These data were used to develop an empirical model relating processing conditions to fiber surface energy. Fiber/ma trix adhesion uas then related to the polar component of the surface e nergy by means of the single-fiber fragmentation test.