Quality assessment of artificially aged A357 aluminum alloy cast ingots by introducing approximate expressions of the quality index QD

The mechanical performance of A357 cast ingot aluminuin alloy specimens subjected to 25 different artificial aging heat treatments has been experimentally investigated. For the quality evaluation of the artificially aged alloys, the quality index Q(D), proposed by the authors, has been involved. The index Q(D) interprets quality as the potential of an alloy to offer combinations of tensile strength, ductility, and toughness at certain levels of values. The evaluation of the alloy quality using Q(D) relies on the availability of the materials tensile flow curve. To facilitate the exploitation of Q(D) for quality assessment, approximations of Q(D) are developed. In the proposed approximations, Q(D) is formulated as a function of ultimate tensile strength, yield strength, and elongation to fracture, or alternatively, as a function of Rockwell hardness E and Charpy impact energy values. Accurate estimations of the quality index Q(D) are compared against Q(D) values obtained by using the proposed approximations.