Evaluation of structure and properties of welded joint of magnesium alloy EZ33A-T5

In recent years, improvement of casting magnesium alloys welding technology has resulted in an increase in the number of publications on this topic. The symptom of this trend is to replace traditional construction materials of magnesium alloys. Magnesium alloys of Mg-Zn-RE-Zr group are used in the automotive, aerospace and defense industries, mainly as gravitional casts to sand moulds or die-casting. Casting defects often appear in these casts (misruns, micro-shrinkage, cracks). The welding technologies are most often applicable to repair of casts, mainly nonconsumable electrode welding in the inert gas cover. The premise of this research work was to define structure and mechanical properties of welded joints of magnesium alloy EZ33A-T5. For this purpose, were attempted trails welding and conducted non-destructive testing, metallographic and strength mechanical tests allowing to assess the properties of welded joints. Evaluation of properties of welded joints was possible by carrying out welding trials and execution of non-destructive tests and metallographic. Research of the microstructure was used with the methodology and test procedures for the quantitative evaluation of the structure of welded joints which was developed in the Department of Materials Science of Silesian University of Technology.