Abstract
Factors that influence the tensile mechanical properties of Al-7Si-Mg alloys A356/7 are critically analyzed. Different casting methods (SSM-HPDC, gravity die casting and investment casting), chemical composition variations and different temper conditions are considered. It is shown that the casting method employed has an influence on the primary α-Al structure, but does not influence the age-hardening response. The most important elements that influence mechanical properties are magnesium and iron. An equation to convert Vickers hardness to 0.2% proof stress in different temper conditions using the strain hardening exponent is proposed. Linear correlations between hardness, strength and (at% Mg-content available for precipitation hardening)1/2 are found. It is shown that ASTM Standard B969-10 needs to be revised.
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Möller, H., Govender, G., Stumpf, W. (2012). Factors Influencing Tensile Mechanical Properties of Al-7Si-Mg Casting Alloys A356/7. In: Suarez, C.E. (eds) Light Metals 2012. Springer, Cham. https://doi.org/10.1007/978-3-319-48179-1_79
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DOI: https://doi.org/10.1007/978-3-319-48179-1_79
Publisher Name: Springer, Cham
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