| Autor: |
HUANG, Y., ZHANG, Y. M. |
| Předmět: |
|
| Zdroj: |
Welding Journal; Oct2011, Vol. 90 Issue 10, p183-190, 8p, 2 Color Photographs, 7 Black and White Photographs, 2 Diagrams, 6 Graphs |
| Abstrakt: |
Laser-enhanced gas metal arc welding (GMAW) is a recent modification of conventional GMAW that applies a relatively low-power laser to the droplet. A systematic series of experiments were designed and conducted to test this modification. A highspeed camera recorded the metal transfer process during each experiment. The behaviors of the laser-enhanced metal transfer process observed from high-speed images were analyzed using the established physics of metal transfer. The characteristics and uniqueness were identified. In all experiments, the laser was found to affect the metal transfer process as an additional detaching force that tended to change a shortcircuiting transfer to drop globular or drop spray, reduce the diameter of the droplet detached in drop globular transfer, or decrease the diameter of the droplet such that the transfer changed from drop globular to drop spray. In addition, this force also provided an effective method to minimize the wandering of the droplet of a relatively large diameter and thus to control the location where it merged into the weld pool. As a result, the uncontrolled drop globular transfer in conventional GMAW as characterized by large droplets and poor weld formation was changed to a controlled drop globular process with improved droplet directionality and weld formation. The large current range associated with drop globular transfer, which required pulsing to change to spray transfer for practical applications, could now be used without pulsing. Desired heat input and current/arc pressure waveforms may thus be delivered by GMAW through laser enhancement. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
|
