Research of the electroless Cu plating on the surface of tungsten powders

The effect of the main process parameters on the electroless Cu plating on the surfaces of the tungsten powders were systematically studied in this paper for developing high performance products contenting tungsten by the orthogonal experiment and the means of SEM, XRD, EDS, and so on. The results showed that: When the temperature was fixed, the significance influence on the solution stability of the electroless Cu plating of the factors decreased according to the order: the concentration of hyposulphite>pH>x(Tar^2-/Cu²⁺)>the concentration of formaldehyde, but the significance influence on the plating rate of the factors decreased according to the order: x (Tar^2-/Cu²⁺)>pH > the concentration of formaldehyde > the concentration of hyposulphite. The better electroless processing was proposed as follows: CuSO₄. 5H₂O. of 8 g/L, KNaC₄H₄O₆ · 4H₂O of 28 g/L, EDTA of 0.75 g/L, NaOH of 8.5 g/L, hyposulphite of 10 mg/L, formaldehyde of 7.5 ml/L, pH value of 12 and the plating temperature about 40°C. Under this optimum conditions of the scheme, the Cu electroless platings were successfully prepared on the surfaces of the tungsten powders.