UNIDIRECTIONALLY CARBON FIBER-REINFORCED HIGH-STRENGTH COMPOSITE MATERIAL

摘要

PURPOSE:The titled lightweight composite material of excellent strength, comprising a specified carbon fiber and a matrix resin. CONSTITUTION:A prepreg is obtained by impregnation a carbon fiber having a 1.5mu-thick surface layer whose perfectness of crystal is on level with that of the fiber core, said surface layer having a 0.2mu-thick or below super-thin outer layer whose perfectness of crystal is low as compared with that of the fiber core,a tensile strength at a fiber volume rate of 70%=370kg/mm2, a tensile strength of a resin-impregnated strand =600kg/mm2, a content of heat- decomposable organic matter of 0.05-0.5wt%, and a ratio of functional group content (OIs/CIs) detected by X-ray photo-electron spectroscopy of 0.1-0.4 with a matrix resin (e.g.., epoxy resin) or a tensile elongation at break (JIS-K-7113)=3.0 (e.g., epoxy resin). Several to several tens of such prepregs are laminated and heated to cure the resin.