Quality evaluation of A357 cast aluminum alloy specimens subjected to different artificial aging treatment

The effect of different artificial aging heat treatment on the quality of A357 alloy cast ingot specimens is evaluated. The experiments include artificial aging of the specimens at 155, 175 and 205 °C for various aging times. The dependencies of hardness and tensile properties of the aged alloys on the aging conditions are derived. Rockwell hardness and yield strength could be correlated using a linear function. The material quality is evaluated such as to be application-specific. By relating quality to yield strength quality could be assessed using the Rockwell hardness measurements. To account in quality evaluation also for tensile ductility quality indices are exploited. The dependencies of the involved quality indices on the aging conditions are derived. Same values of the same quality index are found to correspond to different combinations of tensile properties. The quality index QD proposed by the authors is exploited to devise quality maps; they involve iso-quality lines and the corresponding combinations of tensile properties. A quality map for the cast ingot of A357 alloy is presented. The map may be exploited to select the aging conditions such as to tailor the alloy properties to a certain engineering application.