ABSTRACT
Al-Si-Mg alloys are currently the most popular alloys for obtaining commercial castings, because the mechanical properties of these materials can be improved by heat treatments. However, it should be noted that in cast aluminum alloy parts, porosity is the most frequently occurred defect. This defect usually results in poor mechanical properties. In this sense, the present study aims to analyze the influence of the porosity fraction on the mechanical properties of ultimate tensile strength, specific deformation and hardness in as cast and thermally treated Al-Si-Mg alloy. For that, it was obtained by natural casting and solidification process, an alloy having the following chemical composition: Al-6.5% Si-0.6% Mg. From the basic alloy were obtained ingots with and without degasification process with hexachloroethane pellets. The ingots produced were subjected to thermal treatments of solubilization and subsequent artificial aging. Transverse samples were drawn along the length of the ingots for analysis of porosity fraction and determination of mechanical properties. With the results found in the analysis of porosity and the mechanical tests of tensile and hardness, it was measured the influence of the percentage of porosity on the variation of the mechanical properties.
Keywords
Al-Si-Mg alloys; Solubilization and aging; Porosity; Mechanical Properties