Effect of casting parameters on porosity in LFC

Abstract

Cast aluminium alloys often contain microstructural defects resulting from the casting process such as porosity. Developments of Lost foam casting (LFC) process is considered as one of the most rapid in casting technology owing to its unique advantages on energy savings and capabilities to produce castings with thin sections. In the present research, experimental investigations in lost foam casting of aluminium-silicon cast alloy, LM6, were conducted. The main objective of the study was to evaluate the effect of different pouring temperatures, slurry viscosities, vibration times and sand sizes on the porosity of castings. A stepped pattern was used in the study and the focus of the investigations was at the thinnest 3 mm section. A full 2-level factorial design experimental technique was employed to plan the experiment and subsequently identify the significant factors which affect the casting porosity. The result shows that increasing in the pouring temperature decreases the porosity in the thin-wall section and finer sand size is more favourable than coarse size for LFC mould making process.