Study on the Analysis of Restrike Pattern and Radial Spectrum of AC Arc Discharge based on the Electrode Material

In this study, we designed and fabricated a system based on IEC-62606 and UL-1699 such that stable arc discharge could be produced. AC arc discharge was performed to interpret the restrike pattern and radiation spectrum according to the electrode material. In the voltage waveform analysis of flat copper electrodes, it was analyzed that the accompaniment cycle of the negative waveform was more unstable than the half cycle of the positive waveform. We observed that the radiation spectrum of copper electrodes occurred in the ultraviolet and visible light regions. Moreover, the voltage waveform of the carbon electrode was found to be similar to the pattern produced by the copper electrode. However, we observed that the restrike generated at the half cycle of the negative waveform was produced relatively faster. The radio spectra were strongest near 589 nm, 671 nm, and 766 nm. AC arc discharges using copper electrodes and carbon electrodes were found to be between the arc-discharge patterns of copper electrodes and carbon electrodes. It has been proven that depending on the material of the electrode, there are differences in voltage list like, current patterns, and radiated spectra bands.

Determination of hafnium in zirconium materials

An arc atomic emission technique of hafnium determination in zirconium is developed and tested. The study was carried out on a PGS-2 spectrometer equipped with MAÉS analyzer and information processing software «Atom 3.3». («VMK-Optoélektronika», Novosibirsk). Excitation of spectra of pre-oxidized metal was carried out using a medium-frequency generator «Vesuvius» («VMK-Optoélektronika», Novosibirsk). Analytical line of hafnium was free of spectral overlap with the lines of zirconium. We have set a current of the AC arc discharge (20 A), exposure time (30 sec) and the form of the electrode into which the sample is placed («narrow crater») are selected. The effect of buffering additives (graphite powder, bismuth fluoride) on the intensity of the analyte lines was studied. It is shown that high sensitivity of the analyte is observed for oxidized material without additives. Reduction of the random error attributed to the influence of conditions of spectrum excitation and sample preparation is achieved using the intensity ratio of the analyte line and zirconium as an analytical signal. Recommendations regarding preparation of the samples for calibration are given. The lower limit of the determined concentration is 0.01% with a relative standard deviation in repeatability 3%.

Characterization of 12-Phase AC Arc Discharge and Glass In-Flight Melting Behavior

Thermal plasma of 12-phase AC arc was successfully developed and applied in the field of glass in-flight melting, and the arc discharge behavior was characterized by image analysis. The effects of sheath gas flow rate on arc discharge and melting behavior of granulated glass raw material were investigated. Results show that different sheath gas flow rates lead to various arc discharge and high-temperature region. The fluctuation of luminance area ratio and coefficient of variation reflects the change of arc discharge behavior. As the sheath gas flow rate increases, the ratio of luminance area decreases and the center temperature of arc increases. The vitrification degree of glass raw material is mostly dependent on the center temperature of arc, higher center temperature and more vitrification degree.