Resistance To Impact Properties And Properties Evolution Of Carbon Fiber Reinforced Plastic After Ultraviolet Radiation

Carbon fiber reinforced polymer (CFRP) composites which possesses manyexcellent properties, have been widely used in many areas, in China it is mainly used inaerospace field. The standards of materials used in aerospace industry are so strict thatmuch more comprehensive research is needed. In natural environment, the ray of solarhas deep effect on the structures and properties of CFRP, and ultraviolet (UV) is themost active. So it is necessary to study how UV affects CFRP. What is more, impactdamage which is susceptible to the environment severely limits the excellentperformance of CFRP, low energy impact can cause seriously hidden security dangerespecially. Therefore, the comprehensive consideration of the effect of ultravioletradiation and impact on composite materials is of great guiding significance for theapplication of CFRP in various fields.In this article the tests of the CFRP laminated plates samples which is made ofG803woven carbon fiber as reinforcement and914epoxy as matrix contain UVradiation test and low energy impact test mainly. Besides, the effect of ultraviolet UVradiation to CFRP laminated board and the mechanical property of it after ultravioletradiation are studied. The state of low energy impact of CFRP laminated plate damageand the mechanical properties of it after the superposition of impact and UV radiationare in the consideration.The results show that silver craze and resin wear can be observed on the surface ofCFRP laminated plates, mass loss and a decline of hardness and curing degree are alsoaccompanied. XPS analysis shows that the mole content of C-C will reduce after UVradiation for a long time; it is22.02%after480h. FTIR analysis shows that there is nonew functional group no new functional group, but the intensity of all functional groupsdecreased relatively. The bending strength of CFRP laminated plates changedsignificantly, for240h radiation increased by8.99%, and the time increased again, thestrength reduce. It is below original strength after480h, and the change of tensilestrength is not clear.When low energy impact acts on the CFRP laminated plates, the damagemorphology of its surface is matrix cracks and potholes, back surface is fiber fracturemainly, and inside is laminated separation between the layers which is more obviousthan others. As the impact energy increases, the damage is more serious, the depth ofthe potholes and the damage area magnify. But indentation rebound phenomenon whichmeans the depth of the potholes is smaller over time is observed. The effect of impacton the mechanical properties CFRP laminated plates is greater than that of UV radiation.The greater impact energy and the longer UV radiation, mechanical properties of CFRP laminated plates come down faster, the resistance to impact properties dropped. Whenthe samples are impacted by15J is radiated by UV for480h, the tensile strengthdecreased by47.60%and the bending strength decreased by60.47%.