Structure of butt joint of as-cast magnesium alloys

The article presents a structural analysis of joints of as-cast magnesium alloys created using three joining methods: friction stir welding, CO2 laser welding and electric arc welding in inert gas shielding using tungsten electrode (TIG). The macro- and microstructures of the butt joints have been evaluated using an optical microscope with a digital image recording system. Two types of magnesium alloys were used in the research: AZ91 and AM-Lite, the main alloying elements of which are zinc and aluminium. The starting material consisted of cast ingots milled to a specific dimension and then cut into plate samples with a thickness of 3 mm. The subsequent analysis showed that it is possible to achieve high-quality joints of magnesium alloys. However, trace quantities of pores have also been found. © 2015, © 2014 Taylor & Francis.