Preparation of Al‐Dy core‐shell particles by electron beam treatment of Al powder with consequent magnetron deposition of Dy film

Abstract

• A new method was proposed for coating a commercial aluminum powder by Dy. • Low-energy high-current electron-beam treatment and magnetron sputtering were used. • Surface smoothing and cleaning were detected after electron-beam refinement. • The average size of powder particles increases with the number of e-beam pulses. • Rolling and shaking of powder during the treatment causes uniformity of deposition. The paper presents a new method for coating commercial metal powders with rare‐earth elements (REE). This method consists of a two‐step treatment of a metal powder in a single vacuum cycle, namely the pulsed irradiation above the melting point by a low‐energy high‐current electron beam with subsequent magnetron sputtering of REE. This research reports the preparation of Al‐Dy core‐shell powder with an average diameter of particles of 40 µm. A powder holder system, providing rotary agitation and shaking of powder, was used to guarantee the uniform processing of each particle. It was established that electron beam irradiation leads to smoothing and cleaning the Al particles from surface oxides. With an increase in the number of pulses, the uniformity of processing increases; however, an increase in the average particle size occurs. Subsequent magnetron sputtering allows completely coating the surface of processed powder with dysprosium. The proposed method can be suitable for fabricating different metal‐REE core‐shell powders with necessary changes in processing parameters.