Influence of Mg additions on solidification and performance of B206-type aluminum castings of high Fe and Si contents

Abstract

The role of magnesium content, which varies from 0.2 to 0.6% (% by mass), and of high iron and silicon concentrations (Fe≈0.3%, Si≈0.3%) in B206 aluminum alloys were studied. Microhardness measurements were performed on samples prepared from fractured tensile specimens that were served for microstructural characterization as well. The results of mechanical testing showed that the properties are highly influenced by the iron to silicon ratio and the nominal concentration of magnesium. The best properties were obtained for investigated alloys of low iron and silicon concentrations with a ratio close to one, in agreement with results obtained by solidification study. The addition of magnesium, in specific amount, leads to an increase in the 0.2% elastic stress and without significant effect on the microhardness of alloys studied.

Keywords:

• B206 alloys
• mechanical properties
• microstructure characteristics