A study of porosity quantification techniques and pore morphology in aluminum alloy castings.

摘要

The amount and morphology of porosity in aluminum A356 step bar castings and in thin section, aluminum 356 castings were studied. The uncertainty of the two porosity determination methods and two theoretical density determination methods, performed using the equipment in the Mechanics and Materials Laboratory at Mississippi State University, were determined. Similar counter-gravity castings and conventional castings were compared in terms of their percentage porosity. It was found that, in the thin section castings, the percentage porosity increased with increasing section thickness and the theoretical density also increased with increasing section thickness. The traditional casting method produced castings with the lowest percentage porosity. In the step castings, the percentage porosity and the maximum pore size increase with increasing section thickness, and the area weighted shape factor decreases with increasing section thickness. Strontium modification was found to increase percentage porosity and decrease pore shape factor in the step castings.