Investigation of the Mechanical Properties of Improved Carbon Fiber Composite Materials

摘要

Tension, compression, shear, notch, impact, and fatigue tests were performed on 12 carbon fiber composite materials, ranging from standard carbon fiber reinforced epoxy systems to high strain and intermediate modulus carbon fibers with toughened epoxy, bismaleimide, and thermoplastic matrices. The improvement in mechanical properties of composite attainable through the use of these improved materials depends on the type of fiber and resin and their compatibility in the composite, as well as the interface between them. Thus improved materials should be selected on their overall system performance rather than individual fiber and resin behavior. None of the improved materials has increased compressive strength, particularly in the critical hot/wet and notched case, although most prove to be tougher than the standard materials. All of the tougher materials are more fatigue sensitive when tested in unidirectional form. The thermoplastic based system has the greatest resistance to impact, but the poorest fatigue performance and the properties of + or - 45 laminates show sensitivity to the rate of cooling after molding.