... iron and steel foundries, Lost-foam, Precoated sand;, Sodium silicon sand , Resin sand, Precision casting etc. Advantages:Spherical grain, ... refractory, low density, neutral materials Application:Waterglass bonded sand, resin bonded sand, precision casting, Expendable Pattern Casting (EPC), Copper ... : 1.1 max, similar to ballPacking density: 1.95-2.05 g/cm3Refractoriness: 1790 C minThermal expansion: 0 ...