Improvement of Collapsibility of Sodium Silicate Bonded Cores for Aluminium Casting

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 ۵% sand size bauxite has the best effect on both gas strength and de-coring ۹۸.۵% silica content sand with ۷۰-۹۰ AFS No. with ۴% sodium silicate is used. The results indicate that although very good collapsibility is achieved by ۲% wood flour, its low gas-strength leads the casting towards various defects.