The dynamics of droplet formation and detachment in gas metal arc welding
Experimental measurements of gas metal arc welding are required for the development and confirmation of models of the process. This paper reports on two experiments that provide information for models of the arc physics and of the weld pool dynamics. The heat transfer efficiency of the spray transfer mode in gas metal arc welding was measured using a calorimetry technique. The efficiency varied from 75 to 85%. A special fixture was used to measure the droplet contribution, which is determined to be between 35 and 45% of the total input energy. A series of experiments was performed at a variety of conditions ranging from globular to spray to streaming transfer. The transfer was observed by taking high-speed movies at 500 to 5000 frames per second of the backlighted droplets. An automatic image analysis system was used to obtain information about the droplets including time between detachments, droplet size, and droplet acceleration. At the boundary between the globular and spray modes, the droplet size varies between small droplets that melt off faster than average, resulting in a smaller electrode extension, and large droplets that melt off slower than average, resulting in an increase in the electrode extension. 5 refs., 4 figs., 2 tabs.
- Research Organization:
- EG and G Idaho, Inc., Idaho Falls, ID (USA)
- Sponsoring Organization:
- DOE/ER
- DOE Contract Number:
- AC07-76ID01570
- OSTI ID:
- 6336739
- Report Number(s):
- EGG-M-90058; CONF-9009258-2; ON: DE91006130
- Resource Relation:
- Conference: Modeling of casting, welding and advanced solidification processes engineering foundation conference, Davos (Switzerland), 16-21 Sep 1990
- Country of Publication:
- United States
- Language:
- English
Similar Records
Sensing of metal-transfer mode for process control of GMAW (gas metal arc welding)
Derivation and calibration of a gas metal arc welding (GMAW) dynamic droplet model