CUMI’s synthetic fused alumina produced by controlled fusion of special alumina with other raw materials ensure low bulk density (1.7 vs 2.9 g/cc) and high refractoriness (PCE of 18500C +). This material exhibits very low thermal expansion coefficient (7.2x 10-6/0C) which makes it a perfect substitute for zircon sand in foundry application. The crystal structure enables the product to exhibit low thermal conductivity compared to the regular fused aluminas. This property helps the material to perform at par with zircon sand in cooling process of castings. The thermal and chemical stability of the material ensures very good surface finish and makes the mould fusion free. This will give a better performance in the areas of lettering, riser necks, flange necks etc.
White Fused Alumina is used for making slurry for investment castings. High purity of this material is desired for castings where controlled crystallization is important. CUMI’s low soda alumina is perfect fit for this application. This material is also used for making cores and inserts in foundries for aerospace and power industries.