Preparation and microwave properties of Ni–SiC ultrafine powder by electroless plating

Electroless nickel plating on SiC ultrafine powders with hydrazine hydrate as reductant was studied. The Ni coating was carried out at 90 °C with the molar ratio of [N2H4 · H2O]/[Ni2+] = 2, the concentration of [Ni2+] = 0.25 M and pH 9.6. Scanning electron microscopy (SEM) reveals that Ni–SiC ultrafine powders are of nearly sphere-like shape and are about 300–400 nm in diameter. X-ray powder diffraction (XRD) patterns show that the nickel powder is cubic crystallite. The complex dielectric constant and complex permeability of ultrafine Ni–SiC powder-paraffin wax composites were measured by the rectangle waveguide method. It shows that the dielectric loss is less than 0.2, and the magnetic loss about 1–2 in 8.2–12.4 GHz for prepared Ni–SiC ultrafine powders.