Fiber Dispersion And Conductive Performance Experimental Research On Carbon Fiber Cement-based Composites

Carbon fiber cement-based composites(CFCC) is a kind of smart characteristics of intelligent composite material,which mixed by chopped carbon fiber and composite cement base material.Whether Carbon fiber can be evenly dispersed or not is one of the key factors to decide the stability of CFCC ’s conductive performance and agility characteristics in the preparation of CFCC.In addition, the mechanical properties of cement base material will be affected by mixing carbon fiber in it.In order to get good dispersibility,conductivity and related mechanical coupling of carbon fiber cement-based composites, this article works on the experimental research dispersion of carbon fiber in cement matrix, the conductivity of CFCC and related mechanical properties.The main research contents follows:(1)Adopting new mix slurry method and hardening of the specimen resistance test method to study the the influence of the carbon fiber dispersion in the cement matrix which caused by three kinds of dispersants(MC, CMC, HEC) and the amount of these three dispersants, the experimental results show that HEC dispersant on the carbon fiber dispersion effect is best, and the optimum volume of HEC added into the cement matrix is 0.6%.(2)To study the effects of carbon fiber surface treatment on the morphology of carbon fibers, carbon fiber dispersion, carbon fiber cement mortar(CFRM) internal interfacial bonding properties and CFRM mechanical properties, this paper treated the surfaces of carbon fiber with oxidation respectively by using of two oxidation solvents(nitric acid and sodium hypochlorite solution). The experimental results indicates that, the oxygen-containing functional groups on carbon fiber surface were increased and the infiltration was improved; furthermore, there are three CFRM specimens,one was made from the carbon fiber which haven’t handled with any liquor the other two were made from the carbon fiber whose surface was treated respectively with concentrated nitric acid and sodium hypochlorite, and we can obtain the maximum flexural strength value of CFRM is the one whose carbon fiber was treated with concentrated nitric acid, and followed by sodium hypochlorite. In a word, the fiber surface oxidation treatment can not only improve the invasive of fiber surface and carbon fiber dispersio n performance, but also improve the flexural strength of CFRM.(3)Researching the effect of sand cement ratio, curing age, dry wet environment on CFRM ’s conductivity based on the study of the carbon fiber’s dispersion. Finally studied the conductivity and compressive strength of CFRC which influenced by different particle size of coarse aggregate. The experimental consequence indicates that there exists the largest particle size of coarse aggregate effects: when the aggregate particle size is 16 mm, CFRC’s conductivity and compressive strength reached the maximum value.