Experimental study of cathode spot motion and burning voltage of low-current vacuum arc in magnetic field

This experimental study dealt with cathode spot (CS) motion and the burning voltage of a low-current vacuum arc with electrodes of HCOF Cu and with a composition of CuCr30, subjected to a magnetic field. Arcs with current of I/spl ap/30 A burned in axial and transverse fields as well as with the induction vector inclined at an angle 5/spl deg/

I. Introduction

Some integral characteristics of a low-current arc in vacuum are yet to be studied in detail, notwithstanding the hundred years' history of research into this kind of arc discharge. Among numerous works, whose results are summarized in a number of monographs and reviews, in particular [1]–[4], we note those where the study concerned the results of the action of a magnetic field on the burning voltage of an arc on a cold cathode and the motion of its cathode attachment, the so called “cathode spot” (CS). Fig. 1. Schematic of the geometry of the experiment.