Preparation Of Low Emissivity Material By Electroless Nickel Plate

In this paper, the characteristics of the electroless nickel plating, the composition and fuction of the plating solution were introduced. At this base the low emissivity material was successfully prepared by the electroless plating method .the sample detected by EDXA, SEM, AES, IFR.In order to obtain reasonable processing parameters of electroless nickel plating, the influences of the concentration of Ni2+ and H2PO2- and pH, temperature on the deposition rate were studied. It was found that concentration of both NiSO4 6H2O and NaH2PO2 H2O varied from 25g/L to 35 g/L, the pH of solution varied from 4.5 to 5.0, and requisite mount of stabilizer was added, and the reaction temperature was about 80. the composition of the plating, the plating thickness and the change of the particle before and after plating were analyzed . It was found that the infrared emissivity was decreased from 0.89 to 0.70, and the wave absorbability of radar has not change.To obtain light radar wave absorbing materials, the electroless nickel plating on hollow glass beads and mica was studied. After pretreatment of coarsing, sensitivzed, activation, and reduction, the hollow glass beads and mica powders were plated with nickel. The photograph of SEM showed that its surface have homogenously coated with nickel, although the hollow glass beads were crashed by agitation and heating. After pretreatment and nickel plating, the dispersity of mica powders evidently improved and the infrared emissivity decreased from 0.85 to 0.43, and has certain wave absorbability of radar.The relationship between the concentration of stabilizers, the rate of agitation, the concentration and series of the complex agents and the deposition rate was also studied in this paper.