Correlation between Tensile⁄Shear Fracture Strains and Pore Sizes in a Cast Aluminum Alloy

In this paper, an attempt is made to correlate the material ductility under tensile⁄shear loadings and the pore size in a cast aluminum alloy by sufficient experimental data. Thirty conventional tensile tests on round bar specimens and thirty shear fracture tests on butterfly-like flat specimens are conducted. Pores on each fracture surface are identified using a scanning electron microscopy and characterized in terms of the projected area of the largest pore, the chord length of the largest pore, and the total area of all of the pores on each fracture surface. It is found that the correlation between the tensile fracture strain and the area of the largest pore can be well correlated with a linear function, compared to the total area of all pores and the chord length of the largest pore. Meanwhile, this study reveals that a power function gives a reasonable fitting for the shear loading case in terms of the area of the largest pore.