Heat Treatment of AlSi7Mg0.3 Aluminium Alloys with Increased Zirconium and Titanium Content

The paper compares changes in the structure and mechanical properties due to the synergistic effect of alloying elements Zr and Ti.It is assumed that by increasing the content of Zr and Ti in the aluminium alloy, better mechanical properties will be achieved.Paper focuses on description of the differences between the samples casted into the shell mold and the metal mold.Main difference between mentioned molds is a different heat transfer coefficient during pouring, solidification and cooling of the metal in the mold.The main goal was to analyse the influence of Zr and Ti elements and compare the mechanical properties after the heat treatment.Curing and precipitation aging were used during the experiment.The effect of the elements on AlSi7Mg0.3alloy created differences between the excluded Zr phases after heat treatment.Evaluation of the microstructure pointed to the decomposition of large predominantly needle Zr phases into smaller, more stable formations.