The influences of different factors on the descaling effects in removing oxide layer on metal surface by vacuum arc

Abstract

Vacuum arc descaling technique is a dry and green substitute for the traditional acid-washing and mechanical cleaning technique widely used in the metallurgical industry. It mainly utilizes the high energy density property and the selective motion property of cathode spots. In this paper, the influences of different factors, mainly the vacuum arc circuit, the protect gas pressure, and the electrode gap distance on the effects of descaling process are investigated experimentally. Experiments are conducted in a vacuum chamber with a protect argon gas pressure of 1–1000Pa. The vacuum arc circuit and the electrode gap distance are set to 25–200A and 10–20mm, respectively. The images of vacuum arc and cathode spots during the descaling process are photographed by a high speed digital camera with an exposure time of 2μs. The photos of cathode surface after descaling are analyzed with the help of the images of vacuum arc and cathode spots captured by the high-speed camera. The influences of different factors on the descaling rate (descaled quality per unit time) and the surface cleanliness of cathode are mainly analyzed.