Yu.V. Tcherkasova - Senior Lecturer, Department «General and Experimental Physics», Ryazan State Radio Engineering University. E-mail: yulka-8282@mail.ru
A.S. Ivanikov - Ph.D. (Eng.), Associate Professor, Department «General and Experimental Physics», Ryazan State Radio Engineering University

In case of creation of switches of a high tension, for example, the high-voltage vacuum-sealed magnetically operated switch, there was a question of research of the development mechanism of the phenomena at the time of switching of contacts to increase the breakdown strength providing reliability and quality of maintenance of electronic instruments. For this purpose it can be demanded evaluating a role the prebreakdown of currents in development of electrical breakdowns when switching electrical circuits by low-power high-voltage switches and to consider that currents of autoelectron emission and their accompanying phenomenon, are a basic reason of electric discharge. For search of solutions of this problem the method was developed, at the heart of which lies calculation of current of autoelectron emission with use of the equation of Fowler-Nordheim. In order to estimate the gain factor used in this equation, the contact surfaces from tungsten coatings applied by various methods were investigated, using an atomic force microscope. The received results allowed to evaluate the area of the emitter and gain factor, depending by the type and the form of microleges. Also a computer model of the mechanism of development of electrical breakdown, which significantly expanded assess the impact of various factors on the process of discharge was created. During researches it was clarified that the main phenomena, which define a breakdown strength of high-voltage vacuum-sealed magnetically operated switches, is autoelectron emission with further development of electrical breakdown in couples of material of the anode.