镀镍碳纤维改性水泥基材料的力学性能及耐久性研究OA

The surface of carbon fiber is smooth and it is inert,which results in poor compatibility with cement-based material.The surface properties of carbon fiber can be improved by electroless nickel plating.The surface ele-ments and tensile strength of nickel-plated carbon fiber were characterized,and the nickel-plated carbon fiber modi-fied cement-based material were prepared.Meanwhile,the mechanical properties,crack resistance,impermeability and frost resistance of nickel-plated carbon fiber modified cement-based materials were studied and compared with carbon fiber modified cement-based materials.The interfacial modification mechanism of nickel-plated carbon fiber/cement based material was analyzed by SEM.The results show that,compared with carbon fiber,nickel-plated carbon fiber exhibits higher surface oxygen content and greater tensile strength;it provides better improvement in the mechanical properties and durability of cement-based materials as well as superior dispersion in the matix,with an optimal content of 0.9%.With this fiber content,the flexural strength and compressive strength of the cement-based materials increase by 32.88%and 26.61%,respectively,while the total cracking weight,water seepage height,mass loss rate,flexural strength loss rate,and compressive strength loss rate decrease by 34.76%,53.19%,57.41%,51.29%,and 45.42%,respectively.Numerous pores are observed at the interface of carbon fiber/cement-based material,but the interface of nickel-plated carbon fiber/cement-based material is well bonded.The oxygen element on the surface of nickel-plated carbon fiber improves its hydrophilicity,and the nickel coating enhances its mechan-ical interlocking force with cement-based material.