Study On The Stress Sensibility Of Carbon Fiber Reinforced Polymer

Carbon fiber reinforced polymer composite materials(carbon fiber reinforced polymer,in sort of CFRP)possess a series of excellent characteristics,such as,high strength,high modulus,enduring high temperature,corrosion resistance,fatigue resistance,creep resistance,electrical conductivity,thermal conductivity and low thermal expansion coefficient.They can carry load as a structural material,but also play a role as a functional material,is a function of structural materials.Currently,it has been widely used in various fields.But for many reasons in the preparation process of CFRP,such as,impurities in the environment,the implementation of imperfect etc.there are different forms of defects in the final products.In the use of complex environment,under variety forms of stress,there may be stress focus on these defects cause many types of impair,such as weak fiber fracture,matrix cracking,the interfacial debonding and shear failure. First induced damage of material and the structure then caused the performance of composite materials decreased.The heterogeneity of CFRP composite materials make fatigue damage is often caused by various forms of portfolio accumulated damage, without any prior warning before its loss normal use,a sudden rupture often lead to incalculable damage.Therefore,there is great significance to study the safe use of CFRP and online health monitoring.In this paper,we initially make a series of CFRP which reinforced by three different forms of carbon fiber and two different kinds of polyester resin as matrix. Study on the relationship between resistivity and strain under tensile condition.The characteristics of three curves all closely related to the woven forms.The resistivitystrain curve under tensile condition of resin composites filler with short cut carbon felt can be fit a line,confirmed the one-to-one relationship between resistivity and strain.This law show that resin composites filler with short cut carbon felt can be used for online health Monitoring.And then examine the usages of electrodes on resin composites filler with short cut carbon felt,the result show that the copper electrodes can effectively reduce the contact resistance between metallic and non-metallic,and the output signal can guarantee stability.The Ohm testing proved that the electric conductivities of these kinds of materials are accordant to Ohm Theorem.This study showed that the resistivitystrain curve will not be changed for the different voltage in the tensile test.We studied the effect of resistivity-strain curve on the different loading rate of the machine in the tensile test.Test a series of resin composites filler with short cut carbon felt,analysis the effect of density and type of resin to the resistivity-strain curves and sensitivity coefficient.Using SPSS regression the parameters,established a mathematical model.