The pulse vacuum-arc plasma generator for nanoengineering application
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The pulse vacuum‑arc plasma generator for nanoengineering application A. M. Zhukeshov1 · A. T. Gabdullina1 · A. U. Amrenova1 · K. Fermakhan1 Received: 22 August 2019 / Accepted: 16 August 2020 © Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract In paper described the results of work on the application of vacuum-arc machine in nanoengineering area. Researches were carried out to optimize the operation of this machine for the synthesis of nanomaterials in low-pressure arc-discharge plasma, plasma diagnosis and production of nanopowders. An electrode system based on the grounded cathode with impulse ignition has been developed. The anode current was measured and the mass output of the product was calculated. Experimental data on energy density were obtained, confirming the presence of plasma focusing on the electrode system axis due to its own magnetic field, the focus value of which reaches about 18 kJ/m2. Powder samples were also obtained in the form of clusters containing the copper particles (up to 98%) and spherical powder with size from 116 nm to 1.2 µm. Homogeneity and dispersion of powder depended on the time of the processes accompanying the deposition. Keywords Pulse plasma processing · Vacuum arc discharge · Plasma diagnostic · Thin film deposition · Nanopowders
1 Introduction Vacuum arc is a promising method for obtaining thin films, ultra disperse powders and nanostructure materials in vacuum [1, 2]. Coating or powder is obtained by direct condensation of vacuum-sprayed cathode material and chemical reaction on the surface of substrate, activated by heating or ionization and gas dissociation of the arc discharge [3–5]. To obtain the vacuum arc an electrode system was used, consisting of anode, cathode and igniter electrode covered with insulating material and located next to cathode. Reliability and long operational duration of vacuum arc sources are directly dependent on the specific case of each problem solved to prevent the breakdown and arc starting. In case of the integrally cold cathode, the work process begins with the ignition of vacuum arc, which forms on cathode surface (target) one or more point emission zones called “microcathode spots”, in which the entire discharge power is concentrated. The local temperature of cathode spot is extremely high (about 15,000 °C), which causes intensive evaporation and ionization of the cathode material and formation
* A. M. Zhukeshov [email protected] 1
al-Farabi Kazakh National University, Almaty, Kazakhstan
of high-speed (up to 10 km/s) plasma flows spreading from cathode spot into surrounding space [6]. In arc-driven accelerators, it is very important to combine the size of anode with the voltage applied relative to cathode, so that the main part of plasma is released outside the electrode boundaries without the electric breakdown to anode. In this condition, anode plays the role of the main accelerating electrode. Therefore, the shape, size and mutual arrangement of the used electrodes (cathode, anode and igniter electrode)
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