Improvement of Collapsibility of Sodium Silicate Bonded Cores for Aluminium Casting


Materials Engineering, Iran University of Science & Technology


This paper examines the compressive strength of sodium silicate bonded cores for aluminum casting with different additives. Various materials are used as additives among which it is found that 5% sand size bauxite has the best effect on both gas strength and de-coring 98.5% silica content sand with 70-90 AFS No. with 4% sodium silicate is used. The results indicate that although very good collapsibility is achieved by 2% wood flour, its low gas-strength leads the casting towards various defects.