This paper presents a method of synthesizing copper powders by electrochemical method with the use of a rotating working electrode. The influence of the rotation speed of the working electrode, the current density, the concentration of copper ions, and the addition of ethylene glycol on the shape, size, and size distribution of the obtained powders were investigated. Properties of the synthesized powders were characterized by scanning electron microscopy (SEM) and X-ray powder diffractometry (XRD). It has been shown that it is possible to obtain copper powders with a size of 1 µm by an electrochemical method using the rotary cathode, in sulphate bath with addition of ethylene glycol as a surfactant. Increasing current density causes a decrease in the average size of the obtained powder particles. The addition of 2.5% of ethylene glycol prevents the formation of dendritic powders. The change in the concentration of copper ions in the range from 0.01 to 0.15 mol/dm3 in the electrolyte did not show any significant effect on the size of obtained particles. However, higher concentrations of copper limiting the presence of dendritic-shape particles. Changing the speed of rotation of the electrode affects both the size and the shape of synthesized copper powder. For the rotational speed of the electrode of 115 rpm, the obtained powders have a size distribution in the range of 0-3 µm and an average particle size of 1 µm. The particles had a polygonal shape with an agglomeration tendency.

To clarify the effect of copper powder morphology on the microstructure and properties of copper matrix bulk composites reinforced with Ni-doped graphene, spherical and dendritic copper powders were selected to fabricate the Ni-doped graphene reinforced copper matrix bulk composites. The Ni-doped graphene were synthesized by hydrothermal reduction method, followed by mixing with copper powders, and then consolidated by spark plasma sintering. It is found that the Ni-doped graphene are well bonded with the dendritic copper powder, whereas Ni-doped graphene are relatively independent on the spherical copper powder. The copper base bulk composite prepared by the dendritic copper powder has better properties than that prepared by spherical copper powder. At 0.5wt.% Ni-doped graphene, the dendritic copper base bulk composite has a good combination of hardness, electrical conductivity and yield strength, which are 81.62 HV, 87.93% IACS and 164 MPa, respectively.