An improved sodium silicate binder modified by ultra-fine powder materials

摘要

This paper presents a new method of modifying sodium silicate binder with ultra-fine powders. Thesodium silicate binder modified by ultra-fine powder A and the organic B can reduce the addition amount of thebinder. The results indicate that the 24 h strength has increased by 39.9% at room temperature and the residualstrength has decreased by 30.7% at 800., compared to the conventional sodium silicate. An available material toimprove the moisture resistance was also found by adding about 2% more inorganic C, and it can increase the moiststrength by 20%. In the end, the microanalyses are given to explain the modifying machanism, i. e., the ultra-finepowder A can refine the sodium silicate binder to avoid holes in the binder bond, which can increase the 24 hstrength at room temperture, and can lead to more cracks in the bond after the molding sand is heated to 800.. Thisis because of the stress caused by the new eutectic complex of modified sodium silicate binder