Effect of oxide fluxes on activation mechanisms of tungsten inert gas process
Authors:
- S. LeconteSLS. Leconte
- P. PaillardPPP. Paillard
- P. ChapellePCP. Chapelle
- G. HenrionGHG. Henrion
- J. SaindrenanJSJ. Saindrenan
- 1 July 2006
- journal article
- Published by SAGE Publications in Science and Technology of Welding and Joining
- Vol. 11 (4) , 389-397
Abstract
Activated tungsten inert gas (TIG) welding, which involves the deposition of an inorganic powder on the metal surface prior welding, improves TIG welding performances in terms of weld bead penetration. Most common commercial fluxes contain halides and oxides. The present paper focuses on fluxes made of oxides. It appears that oxides have two different effects: one on the fusion zone chemistry and the other on the electric arc behaviour. First, oxygen reverses the Marangoni convection movements that become centripetal, contributing thus to increase ‘D’ penetration. On the other hand, oxides may cause an increase in the energy flux density transferred by the arc to the metal. The characterisation of the arc plasma by optical emission spectroscopy suggests that oxides do not increase the arc temperature. It is established that the oxide effects by Marangoni convection appear for a critical value of the welding energy, whereas the oxide effects on the electrical arc exist irrespective of the welding energy value.Keywords
This publication has 10 references indexed in Scilit:
- Effect of fluxes containing oxides on tungsten inert gas welding processScience and Technology of Welding and Joining, 2006
- Sensitivity of Marangoni convection and weld shape variations to welding parameters in O2?Ar shielded GTA weldingScripta Materialia, 2004
- Marangoni convection and weld shape variations in Ar–O2 and Ar–CO2 shielded GTA weldingMaterials Science and Engineering: A, 2004
- Weld shape comparison with iron oxide flux and Ar–O2 shielding gas in gas tungsten arc weldingScience and Technology of Welding and Joining, 2004
- Mechanism and optimization of oxide fluxes for deep penetration in gas tungsten arc weldingMetallurgical and Materials Transactions A, 2003
- Effects of metal vapor on electron temperature in helium gas tungsten arcsMetallurgical and Materials Transactions A, 2002
- Weld Penetration and Marangoni Convection with Oxide Fluxes in GTA WeldingMATERIALS TRANSACTIONS, 2002
- Effects of activating flux on arc phenomena in gas tungsten arc weldingScience and Technology of Welding and Joining, 2000
- Investigation into arc constriction by active fluxes for tungsten inert gas weldingScience and Technology of Welding and Joining, 2000
- Determination of oscillator strengths for UI and UII linesJournal of Quantitative Spectroscopy and Radiative Transfer, 1987