Open AccessStructure of microplasma discharge on titanium surface covered with thin dielectric film
Author(s) -
В. А. Иванов,
M. E. Konyzhev,
A. A. Dorofeyuk,
T. I. Kamolova
Publication year - 2020
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1647/1/012018
Subject(s) - microplasma , titanium , materials science , cathode , dielectric barrier discharge , plasma , glow discharge , dielectric , analytical chemistry (journal) , chemistry , optoelectronics , metallurgy , physics , chromatography , quantum mechanics
The spatial structure of the pulsed microplasma discharge (discharge duration is 100 μs, the amplitude of the discharge current is 200 A) was experimentally studied. The discharge is initiated on the titanium sample surface covered with the thin dielectric (titanium oxide) film with a thickness of ~10 nm. The sample was exposed to the pulsed plasma flow (the plasma density is 2 × 10 13 cm –3 , and the pulse duration is 25 μs). It was found that the microplasma discharge glow has the branched dendrite structure, which consists of a large number of cathode spots (brightly glowing localized formations) randomly distributed over the metal surface. As a result of interaction between the microplasma discharge and the titanium sample, erosion occurs on its surface. The erosion structure is visually “identical” to the discharge glow structure. It was ascertained that the erosion pattern on the titanium surface consists of a large number of individual microcraters with characteristic sizes from 0.3 to 10 μm randomly distributed over an area of approximately 1 cm 2 . All together, these microcraters form the branched dendrite structure. It was also ascertained that the microplasma discharge propagates along the titanium surface covered with a thin dielectric (titanium oxide) film at an average velocity of approximately 70 m/s, and this propagation has a “jumping” character: the plasma of burning cathode spots initiates the excitation of new cathode spots at distances of 3–30 microns from them.