Relationship between internal porosity and fracture strength of die-cast magnesium AM60B alloy

A die-cast magnesium alloy was examined with the use of X-ray tomography. Five tensile samples cut from different locations of a thin-walled, high-pressure magnesium die-casting were analyzed. The size and locations of pores in each sample were obtained from the X-ray tomography data. A critical local strain model was used to predict the fracture properties of the tensile samples. The validity of the model was exhibited by comparison of the predicted results with results from tensile tests. The location of the plane of fracture, the fracture strain, and the fracture stress were predicted to within 8%, 22%, and 11% accuracy, respectively. It was concluded that the local areal fraction of porosity is the primary factor in determining the tensile properties of the magnesium alloy specimens. (c) 2005 Elsevier B.V. All rights reserved.