US A356 and US 413 cast aluminium alloys shrinkage characteristic have been discussed in the present study. Specific volume reduction
leads to shrinkage in castings and it can be envisaged as a casting defect. Finite difference based casting process simulation software has
been used to study the shrinkage characteristic and it is quantified using mathematical formulae. The three dimensional model of the
shrinkage defect has been constructed using CAD application software. Shrinkage characteristic has also been quantified through
experimental validation studies and compared well with casting process simulation. Shrinkage characteristic study and control is essential
for producing defect free castings. Influence of casting shape on the shrinkage characteristic has been studied in this paper.