Abstract
Oxide coating on carbon fiber by ion-plating method was investigated in order to improve the compatibility of carbon fiber (CF) with aluminum (Al). Five oxides such as calcia (CaO), magnesia (MgO), alumina (Al2O3), zirconia (ZrO2) and titania (TiO2), were used for the coating. First, the oxide coatings were evaluated as a reaction barrier between CF and Al. MgO was the best reaction barrier agent among the oxides tested and prevented perfectly the degradation in strength of Al coated CF after heating up to 873 K for 18 ks. CaO and Al2O3 had also fair effect for the reaction barrier between CF and Al and prevented the degradation in strength of Al coated CF after heating up to 823 K. ZrO2 and TiO2, however, reacted with Al and caused remarkably the degradation in strength of CF. Next, the oxide coatings were evaluated as a wetting agent to molten aluminum by SEM observation of the wetting state of molten Al on carbon fibers after heating at 1, 023 K for 3.6ks. The oxides increased the wettability in the following order: TiO2, Al2O3, CaO, MgO, and ZrO2.
