Study On The Magnetic Coatings Of Carbon Nanofibers

Carbon Nanofibers is a new type of carbon materials. Carbon nanofibers have been widely studied in recent years because of their magnificent physical, chemical properties and a wide range of potential applications in structure strengthen material, cell electrode material, electromagnetic wave-absorbing and wave-shielding material. For further improvement of eletromagnetic performance of carbon nanofibers and reinforcement of interfacial strengh between carbon nanofibers and metal or ceramic matrix, metal or alloy coatings are prepared by electroless deposition of Ni-Fe-Co-P alloy.The main contents of the paper are divided into two parts:First, bath composition, operating conditions and stability of solution were investigated by using iron as sample. The influences of the main salts, reducing agent, complexing agent and content of NH₃·H₂O on deposition rate and performance of coatings were studied. The deposition rate of electroless plating were measured by the method of increased mass. The results show that with the increase of the concentration of NiCl₂ · 6H₂O, the deposition rate increased rapidly. But when the concentration of NiCl₂ · 6H₂O exceeded 18 g·L^-1, the stability of electroless solution was decreased, coatings became rough and dark. With the increase of the concentration of CoSO₄ · 7H₂O, the deposition rate decreased at first. When the concentration of COSO₄ · 7H₂O was 16 g·L^-1, the deposition rate achieved minimum data. Then the deposition rate increased gradually, but the stability of electroless solution was decreased and coatings were rough and dark. With the increase of the concentration of (NH₄)₂Fe(SO₄)₂ · 6H₂O, the deposition rate reduced gradually. With the increase of [Co²⁺]/[Fe²⁺], the deposition rate increased gradually.When [Co²⁺]/[Fe²⁺] exceeded 3:1, the performance of coatings declined accordingly. The coatings became dark and easy to fall off. With the increase of [Fe²⁺]/[Ni²⁺], the deposition rate decreased gradually. With the increase of [Co²⁺]/[Ni²⁺], the deposition rate decreased gradually. With the increase of the concentration of complexing agent, the deposition rate increased gradually, and the stability of solution...