| Weld shape variation and electrode protection under Ar-(Ar-O(2)) double shielded GTA welding | |
| S. P. Lu; H. Fujii; K. Nogi | |
| 2009 | |
| Source Publication | Science and Technology of Welding and Joining
 |
| ISSN | 1362-1718 |
| Volume | 14Issue:8Pages:726-733 |
| Abstract | Double shielded gas tungsten arc welding (GTA welding or TIG welding) of an SUS304 stainless steel with pure inert argon as the inner layer shielding and the Ar-O(2) active gas as the outer layer shielding is proposed in this study in order to investigate its effect on the tungsten electrode protection and the weld shape variation. The experimental results show that the inner inert argon gas can successfully prevent the outer layer active gas from contacting and oxidising the tungsten electrode during the welding process. The active gas, oxygen, in the outer layer shielding is decomposed in the arc and dissolves in the liquid pool, which effectively adjusts the active element, oxygen, content in the weld metal. When the weld metal oxygen content is over 70 ppm, the surface tension induced Marangoni convection changes from outward into inward, and the weld shape varies from a wide shallow one to a narrow deep one. The effect of the inner layer gas flowrate on the weld bead morphology and the weld shape is investigated systematically. The results showed that when the flowrate of the inner argon shielding gas is too low, the weld bead is easily oxidised and the weld shape is wide and shallow. A heavy continuous oxide layer on the liquid pool is a barrier to the liquid pool movement. |
| description.department | [lu, s. p.; fujii, h.; nogi, k.] osaka univ, joining & welding res inst, osaka 5670047, japan. [lu, s. p.] chinese acad sci, inst met res, shenyang natl lab mat sci, shenyang 110016, peoples r china.;lu, sp (reprint author), osaka univ, joining & welding res inst, osaka 5670047, japan;shplu@imr.ac.cn |
| Keyword | Double Shielding Weld Shape Marangoni Convection Gta Welding Gas Tungsten Arc Marangoni Convection Activating Flux Stainless-steel Oxide Fluxes Deep Penetration Pool Flow Tig Elements |
| URL | 查看原文 |
| Document Type | 期刊论文 |
| Identifier | http://ir.imr.ac.cn/handle/321006/32160 |
| Collection | 中国科学院金属研究所 |
| Recommended Citation GB/T 7714 | S. P. Lu,H. Fujii,K. Nogi. Weld shape variation and electrode protection under Ar-(Ar-O(2)) double shielded GTA welding[J]. Science and Technology of Welding and Joining,2009,14(8):726-733. |
| APA | S. P. Lu,H. Fujii,&K. Nogi.(2009).Weld shape variation and electrode protection under Ar-(Ar-O(2)) double shielded GTA welding.Science and Technology of Welding and Joining,14(8),726-733. |
| MLA | S. P. Lu,et al."Weld shape variation and electrode protection under Ar-(Ar-O(2)) double shielded GTA welding".Science and Technology of Welding and Joining 14.8(2009):726-733. |
| Files in This Item: | ||||||
| File Name/Size | DocType | Version | Access | License | ||
| 1928.pdf（756KB） | 开放获取 | -- | ||||
Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.
Edit Comment