Effects of Chemical Co-precipitation Process on Coating Quality of NickelCoated Tungsten Carbide Cemented Carbide Powder

Using tungsten carbide (WC) powder and NiCl₂·6H₂O as raw materials, nickel coated WC composite powder (WC-Ni) was prepared by combining chemical co-precipitation process and high temperature hydrogen reduction process. The micro morphology and phase composition of WC-Ni composite powder were characterized and analyzed. The effect of chemical co-precipitation process on the effect of nickel coated WC powder was studied. The results show that under the conditions of proper liquid concentration, temperature and precipitant addition volume flow, by adjusting the nucleation rate of crystal grains, the collision probability between particles and the degree of particle aggregation, it was beneficial to obtain uniformly dispersed and densely coated WC-Ni powder. The optimized process conditions were 0.4 mol·L^-1 NiCl₂+0.2 mol·L^-1(NH₄)₂C₂O₄, the reaction temperature was 50 ℃, and the addition volume flow of precipitant was 0.17 mL·s^-1.