ELECTRON BEAM WELDING OF AUTOGENOUS BUTT-JOINTS FOR AA5083-O ALUMINUM-MAGNESIUM ALLOY SHEET.

Electron beam welding (EBW) is increasingly being used in welding structural metals. The thermal cycles associated with EBW are generally much faster than those involved in conventional arc welding processes, leading to a rather small fusion zone. Complete information on the tensile properties is essential for understanding the joint performance in service. Therefore, experimental investigation was performed on the mechanical properties of EBW welded AA5083- O sheets, using flat tensile specimens. An autogenous single electron beam pass was used to weld butt joints and butt joints with integral backup. The specimens were examined by visual testing, metallography light microscopy, microindentation hardness measurements and a tensile test. The results of the welded tensile specimens were compared to base metal (BM) specimens machined from the asreceived materials. The yield stress of the welded samples is higher and the elongation is lower than the BM. An insignificant narrow heat affected zone (HAZ) was observed. The dendritic microstructure of the fusion zone (FZ) was relatively homogenous and the BM microstructure showed preferred orientation. Slightly higher microhardness values were observed in the FZ and HAZ than in the BM. [ABSTRACT FROM AUTHOR]

Copyright of Annals of "Dunarea de Jos" University of Galati, Fascicle XII, Welding Equipment & Technology is the property of Dunarea de Jos University of Galati and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)