Hits:

Indexed by:期刊论文

Date of Publication:2013-10-01

Journal:OPTICS AND LASERS IN ENGINEERING

Included Journals:SCIE、EI、Scopus

Volume:51

Issue:10

Page Number:1153-1160

ISSN No.:0143-8166

Key Words:Laser keyhole; Behavior; Synchronous observation; Laser-arc welding

Abstract:This paper presents an investigation on effect of electric arc on laser keyhole behavior based on direct observation during pulsed laser-arc hybrid welding process. Direct and synchronous observation of laser keyhole outlet and arc plasma is achieved by means of an assistant illuminating laser and corresponding optical modulation. Experimental results show that after laser pulse action the keyhole outlet does not close immediately and the time depends on the welding parameters. Larger arc current will decrease the existing time of keyhole outlet. Extension of arc plasma column into the laser keyhole gives the pressure to the inner keyhole wall, and consequently hinders the keyhole from collapse, resulting in the longer existence of keyhole outlet. The surface tension of the liquid metal around the keyhole outlet increases due to the extension of arc column into the keyhole, which also prevents the keyhole outlet from collapse. (c) 2013 Elsevier Ltd. All rights reserved.