Effects of the electrode oxidizing potential on underwater wet welds
- Colorado School of Mines, Golden, CO (United States). Center for Welding and Joining Research
Depth greatly affects the chemical composition and mechanical properties of underwater wet (UWW) welds. It is well documented in the literature that as depth increases, the amount of oxygen in the weld increases while the deoxidants decrease in concentration. To understand the influence of oxygen on the characteristics and properties of UWW welds, deposits of electrodes with different oxidizing potentials were studied. The oxidizing potentials of these electrodes were varied through additions of hematite (Fe{sub 2}O{sub 3}) to the covering of a ruffle electrode. No metallic deoxidants were used in the coverings, but MgO was added to one of the oxidizing electrodes as a possible way to control oxygen. The welds were made at 0.5 m of water depth. Chemical analysis showed that increasing oxidizing potential of the electrodes increased the weld metal oxygen content eventually reaching a plateau value of approximately 2,100 ppm. This concentration plateau is determined by the solubility limit of FeO in the liquid iron at the solidification temperature. The MgO addition was sufficient to reduce the oxygen level to 1,700 ppm. The results also showed that the effects of increasing oxidizing potential of the electrode covering on weld metal composition and microstructure are similar to those of increasing water depth. This finding is very significant since it allows for the simulation of deep water weld metal microstructures in shallow waters by controlling the oxidizing potential of the consumables used. Finally, studying the properties of oxidizing electrodes in shallow depths will also be useful in developing welding electrodes for deep waters.
- OSTI ID:
- 27952
- Report Number(s):
- CONF-940230-; ISBN 0-7918-1266-9; TRN: IM9516%%78
- Resource Relation:
- Conference: 13. international conference on offshore mechanics and Arctic engineering (OMAE-13), Houston, TX (United States), 27 Feb - 3 Mar 1994; Other Information: PBD: 1994; Related Information: Is Part Of OMAE 1994. Volume 3: Materials Engineering; Salama, M.M.; Toyoda, Masao; Lui, S.; Dos Santos, J.F.; Kocak, M.; Patterson, E.A.; Berge, S. [eds.]; PB: 438 p.
- Country of Publication:
- United States
- Language:
- English
Similar Records
Hydrogen content of underwater wet welds deposited by rutile and oxidizing electrodes
Use of nickel to improve the mechanical properties of high oxygen underwater wet welds