Optical emission and surface characterization of stainless steel treated by pulsed microwave-atmospheric helium plasma jet

Essam Abdel-Fattah; Ashraf Yehia; Marian Bazavan; Tatsuo Ishijima

doi:10.1140/epjd/e2017-80044-7

2022 Impact factor 1.8

Atomic, Molecular, Optical and Plasma Physics

Eur. Phys. J. D (2017) 71: 178
https://doi.org/10.1140/epjd/e2017-80044-7

Regular Article

Optical emission and surface characterization of stainless steel treated by pulsed microwave-atmospheric helium plasma jet

Essam Abdel-Fattah¹^,2^a, Ashraf Yehia¹^,3, Marian Bazavan⁴ and Tatsuo Ishijima⁵

¹ College of Science and Humanities, Prince Sattam Bin Abdulaziz University, P.O. Box 173, 11942 Al-Kharj, Saudi Arabia
² Physics Department, Faculty of Science, Zagazig University, 44519 Zagazig, Egypt
³ Department of Physics, Faculty of Science, Assiut University, 71516 Assiut, Egypt
⁴ University of Bucharest, Faculty of Physics, P.O. Box, 077125 Mãgurele, Romania
⁵ Research Center for Sustainable Energy and Technology, Institute of Science and Engineering, Kanazawa University, 920-1192 Kanazawa, Japan

^a e-mail: essam29@hotmail.com

Received: 22 January 2017
Received in final form: 28 March 2017
Published online: 4 July 2017

Abstract

A pulsed microwave-excited atmospheric pressure plasma jet MWAPPJ in helium, has been investigated by optical emission spectroscopy OES. Beside helium spectral lines various excited species such as atomic oxygen OI, hydrogen H_α line, N₂⁺ ion and nitrogen molecule species N₂ (C³Π_u) which are responsible for metal surface activation. The rotational T_rot and vibrational temperature T_vib were evaluated using optical emission spectroscopy and their dependences on the pulsed microwave parameters such as duty factor (20–70%) and a repetition rate (4 to 90 kHz) are investigated. Spectroscopic measurements show that, T_rot, T_vib and relative emission intensity of excited species greatly increases with increasing pulse duty factor. Meanwhile they show weak dependences as repetition frequency increased. Surface characterization of the examined stainless steel samples were performed through contact angle, Atomic force microscope AFM and X-ray photoelectron emission spectroscopy XPS. The contact angle decreased from 71° to 20° after pulsed MWAPPJ helium plasma at duty factor of 70% treatment for 30 s, which it is mainly due to incorporation of oxygen-containing functional groups as inferred from XPS results.