PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY
Series: Nuclear and Reactor Constants

since 1971

Русский (РФ)

ISSN 2414-1038 (online)

BEHAVIOR OF PLATINUM ON THE SURFACE OF A SINGLE CRYSTAL POLYHEDRAL TUNGSTEN EMITTER OF THE THERMIONIC CONVERTER

EDN: RIRHND

Authors & Affiliations

Yarygin V.I., Тulin S.M.
A.I. Leypunsky Institute for Physics and Power Engineering, Obninsk, Russia

Yarygin V.I. – Chief Researcher, Dr. Sci. (Tech.), Professor. 1, pl. Bondarenko, Obninsk, Kaluga region, Russia, 249033. Tel.: +7 (484) 399-88-29; e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it..
TulinS.M. – Lead Engineer.

Abstract

The article discusses the experimental results of the research by complex methods of analyzing the properties of the surface, near-surface region and emission-adsorption characteristics in the interelectrode medium of the TIC of the behavior of platinum deposited on W [111] in the form of a film with a thickness of ~3 microns. Discussion of experimental results is carried out within the framework of a consistent physical model of platinum modification of tungsten tungsten single crystal polyhedral gas-phase emission coating W [111] on cylindrical TIC emitters with axial crystallographic orientation [111].
The experimental results described in the article showed that W[111] coatings modified with a platinum film have the following properties:
– platinum forms a near-surface tungsten-platinum alloy in areas with “loose” type (121)-faces and with defective areas in the process of simultaneous surface diffusion of platinum from areas with orientation along the (110)-facet in the area of “loose” faces and volume diffusion platinum into the near-surface regions of “loose” faces;
– tungsten-platinum alloy in the near-surface regions of single-crystal polyhedral tungsten emission coatings ensures their emission homogeneity, corresponding to the vacuum work function of electrons ~5.2 eV and remaining in vacuum and the interelectrode medium of TIC up to a temperature not lower than ~2000 K.

Keywords
thermionic converter, electrode materials, emitter, single-crystal tungsten, platinum, work function of electrons, slow electron diffraction, electron auger spectroscopy

Article Text (PDF, in Russian)

References

UDC 621.311:621.039

Problems of Atomic Science and Technology. Series: Nuclear and Reactor Constants, 2023, no. 1, 1:16