| 摘要 |
PURPOSE:Acrylic carbon fibers are anodized in a specific electrolyte solution, than heat-treated in an inert or reductive atmosphere to product carbon fibers for making composite materials of superhigh strength. CONSTITUTION:Acrylic carbon fibers with an average filament strength of more than 400kg/mm<2> are anodized in an electrolyte solution which contains nitrate ions and is kept over 40 deg.C using the carbon fibers as the anode with a currency of about 50-600coulombs/g of fibers. Then, the fibers are washed with water, dried and heat-treated at 600-1,000 deg.C in an inert or reductive atmosphere to inactivate their surfaces. Thus, although the completeness of crystals are low on the ultrathin outermost layer, the completeness of crystals on the surface layer is substantially at the same level as in the core part of the fibers to give carbon fibers than 600kg/mm<2> strength as a strand which is impregnated with a resin.
|
