Sublimation of graphite in continuous and pulsed arc discharges

Authors

AFSHAN ASHRAF
KASHIF YAQUB
SUMERA JAVEED
SUMAIRA ZEESHAN
RAHILA KHALID
SOHAIL AHMAD JANJUA
SHOAIB AHMAD

DOI

10.3906/fiz-0903-10

Abstract

Sublimation of graphite has been investigated in continuous and pulsed arc discharges. The results of continuous arc discharge between graphite electrodes are compared with pulsed arc discharge between cylindrical Aluminum cathode and annular graphite anode. The sublimed species include monoatomic and diatomic carbon clusters with their relative composition depending upon the mechanism of energy dissipation in graphite electrodes. Diatomic carbon (C_2) is the dominant subliming cluster. Emission spectroscopy of the Swan band system [d^3\prod _g -a^3\prod _u ] of C_2 has been used to investigate the thermodynamic state and to deduce the vibrational temperature (T_{vib}). The vibrational level densities indicate that local thermodynamic equilibrium exists in both types of discharges and T_{vib} \approx 7000-9000 K.

Keywords

Graphite sublimation, continuous arc discharge, pulsed arc discharge, electron collision

First Page

33

Last Page

42

Recommended Citation

ASHRAF, AFSHAN; YAQUB, KASHIF; JAVEED, SUMERA; ZEESHAN, SUMAIRA; KHALID, RAHILA; JANJUA, SOHAIL AHMAD; and AHMAD, SHOAIB (2010) "Sublimation of graphite in continuous and pulsed arc discharges," Turkish Journal of Physics: Vol. 34: No. 1, Article 4. https://doi.org/10.3906/fiz-0903-10
Available at: https://journals.tubitak.gov.tr/physics/vol34/iss1/4