Evaluating structural integrity of cast Al–7%Si–Mg alloys via work hardening characteristics: II. A new quality index

Toughness, as defined by the energy to failure constituted by the area under the true stress–strain curve, of Al–7 wt.%Si–Mg alloys with three different Mg contents (0.20, 0.40, and 0.60 wt.%) was analyzed. Since toughness is markedly affected by the presence of structural discontinuities, a new quality index based on toughness is proposed. The index, QE, can be found by comparing the toughness of the specimen with its threshold toughness, based on the concept of target properties. Threshold toughness is proposed as a target value. The new quality index can be applied to all specimens regardless of their processing history and chemical composition.