Preparation and High-Temperature Performance of Core-Shell Structured Cu@Ni-P@Ag Composite Powders

Abstract

In this paper, dendritic copper powder with an average particle size of 9.941 ± 0.042 μm was synthesized using the electrodeposition method, employing laboratory copper-containing electroplating wastewater as the raw material. The synthesized copper powder served as the substrate for electroless nickel-phosphorus alloy plating, acting as an intermediate layer. Subsequently, electroless silver plating was performed on the surface of the Cu@Ni-P composite powders to produce the Cu@Ni-P@Ag composite powders. The influence of various factors on the properties of these powders was investigated, and the optimal experimental parameters were determined. A comprehensive analysis of the micromorphology and properties of the core-shell structured powder was conducted using various characterization techniques, including XRD, SEM, EDS, TGA, and XPS. The results indicated that the onset oxidation temperature of the core-shell powders, prepared under a 5% ammonia reaction system with 30% silver content, at 50°C and a glucose concentration of 0.4 mol L⁻¹, was approximately 450°C. This finding demonstrates a significant improvement in antioxidant properties compared to Cu@Ag core-shell powders. Additionally, the electrical resistivity of the prepared core-shell structured powders was measured at 9.30 × 10⁻⁴ Ω cm at a high temperature of 400°C.