Ingenieurwissenschaften und zugeordnete Tätigkeiten
Filtern
Erscheinungsjahr
- 2020 (2) (entfernen)
Dokumenttyp
- Zeitschriftenartikel (1)
- Vortrag (1)
Sprache
- Englisch (2)
Schlagworte
- Solidification cracking (2) (entfernen)
Organisationseinheit der BAM
- 9.3 Schweißtechnische Fertigungsverfahren (2) (entfernen)
Eingeladener Vortrag
- nein (1)
In this study, the influence of the welding speed, the arc power, and the laser focal position on the solidification crack formation for partial penetration laser hybrid–welded thick-walled plates was investigated.
The solidification cracking in the weld root is a result of interaction between metallurgical and geometrical and thermomechanical factors.
Experimentally, a direct correlation between the welding speed and the crack number was observed. That is by reducing the welding velocity, the crack number was decreased. The focal position shows also a significant influence on the crack number. By focusing the laser on the specimen surface, the crack number has been significantly diminished.
The wire feed speed showed a very slight influence on the crack formation. That is due to the large distance between the critical region for cracking and the arc region.
The numerical model shows a high stress concentration in the weld root for both components (vertical and transversal).
Numerically, the reduced welding speed showed a strong impact on stress, as the model demonstrated a lower stress amount by decreasing the welding speed.
The metallurgical factors, such as the assumed accumulation of the low-melting eutectics in the weld root, should be a contribution for solidification cracking, where the tensile stress is acting.
Using a novel optical measurement technique together with the OF algorithm, a two-dimensional deformation analysis during welding was conducted.
The OF technique was the first of its kind to provide a measurement of the full strain field locally in the immediate vicinity of the solidification front. The local critical strain and strain rate in vicinity of the solidification front has observed 1.57%, 28 %/s, respectively.