A direct electroless copper (Cu) coating on tungsten powders method requiring no surface treatment or stabilizing agent and using glyoxylic acid (C2H2O3) as a reducing agent was reported. The effects of copper sulfate concentration and the pH of the plating solution on the properties of the prepared W@Cu composite powders were assessed. The content of Cu in the composite powders was controlled by adjusting the concentration of copper sulfate in the electroless plating solution. A uniform, dense, and consistent Cu coating was obtained under the established optimum conditions (flow rate of C2H2O3 = 5.01 mL/min, solution pH = 12.25 and reaction temperature 45.35 ℃) by using central composite design method. In addition, the crystalline Cu coating was evenly dispersed within the W@Cu composite powders and Cu element in the coating existed as Cu0. The formation mechanism for the W@Cu composite powders by electroless plating in the absence of surface treatment and stabilizing agent was also proposed.
展开▼
