Density index ( Metal Cleanliness Indicator )

The density index is used as an indicator of the amount of total porosity present in the Cast condition.

 Density indexing is a process by which we test for and reduce the porousness of our castings. We subject a sample of molten aluminum to a reduced pressure test (RPT), where it is allowed to solidify in a vacuum. The reduced pressure enhances the size of the porosity formed.