The lattice distortion of nickel particles generated by spark discharge in hydrocarbon dielectric mediums

Nickel particles were prepared by the ultrasound-aided spark discharge in pure water and hydrocarbons (kerosene and EDM fluid). The element composition and lattice structure were analyzed by EDS and XRD, respectively. The EDS indicated a high-purity powder was generated in pure water. For hydrocarbons, the carbon was detected as the majority impurity dissolved into the Ni interstitial sites, and the quantitative XRD revealed that the peak positions are lower than those of the corresponding perfect Ni crystal. The d-spacing deviation increases with the effect of ultrasound in hydrocarbons, while the distortion is negligible for pure water. We reported the composition, interatomic distances, and distortion of the Ni particles resulting from C doping. These findings revealed a new method to synthesize the solid solution via the spark discharge.