Ion velocities in direct current arc plasma generated from compound cathodes211102
2013 (English)In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 114, no 21, 213302- p.Article in journal (Refereed) Published
Arc plasma from Ti-C, Ti-Al, and Ti-Si cathodes was characterized with respect to charge-state-resolved ion energy. The evaluated peak velocities of different ion species in plasma generated from a compound cathode were found to be equal and independent on ion mass. Therefore, measured difference in kinetic energies can be inferred from the difference in ion mass, with no dependence on ion charge state. The latter is consistent with previous work. These findings can be explained by plasma quasineutrality, ion acceleration by pressure gradients, and electron-ion coupling. Increasing the C concentration in Ti-C cathodes resulted in increasing average and peak ion energies for all ion species. This effect can be explained by the "cohesive energy rule," where material and phases of higher cohesive energy generally result in increasing energies (velocities). This is also consistent with the here obtained peak velocities around 1.37, 1.42, and 1.55 (10(4) m/s) for ions from Ti0.84Al0.16, Ti0.90Si0.10, and Ti0.90C0.10 cathodes, respectively.
Place, publisher, year, edition, pages
American Institute of Physics (AIP) , 2013. Vol. 114, no 21, 213302- p.
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-103292DOI: 10.1063/1.4841135ISI: 000328635600006OAI: oai:DiVA.org:liu-103292DiVA: diva2:688494