Influence of gas flow rate on spectroscopic characterization of Cu-Zn Alloy plasma by OES

Abstract

     In this work, a plasma jet system generated in a deionized aqueous medium was studied. A locally manufactured copper-zinc alloy with a ratio of 80:20 was used for this purpose, and a bidirectional power supply with a total output of 20 kV and a cutoff frequency of 30 kHz was used. The gas flow rate was varied at 3, 3.5, 4, 4.5, and 5 liters per minute (L/min) while the voltage was kept constant at 13 kV. The emission lines of the copper-zinc alloy elements and gases were determined in the range of 200 to 1000 nm. Key plasma parameters, such as the particle number in the Debye sphere, plasma frequency, and Debye length, as well as the most important parameters, such as electron density and temperature, were then calculated. The study concluded that increasing the gas flow rate increased the plasma emission. The maximum peak for argon gas under the operating conditions used at the highest flow value was 811.5311 nm. Alloy element emissions appeared in the wavelengths between 200 and 300 nm. A decrease in electron temperature was observed with increasing gas flow rate, reaching its highest value at the highest gas flow rate used, reaching 0.703 eV. In contrast, a clear increase in electron density was observed with increasing gas flow rate. This behavior indicates that the interaction between the plasma and the surrounding environment, as well as the ionization dynamics, strongly depends on the gas flow rate. These results provide valuable insights into the role of flow rate in shaping plasma properties such as emission intensity, as well as temperature and electron density, which are critical for improving the performance of plasma-based applications.