摘要 |
<p>Novel compositions are disclosed for the manufacture of gunning mixes and strong castable products for use as monolithic refractory and construction materials which may contain no lime bearing cements. Bonding is based on the setting reaction of fumed silica with an alkali metal silicate, preferably a particulate sodium or potassium silicate that slowly dissolves in water, such as an anhydrous sodium silicate having a SiO2:Na2O molar ratio of 3:1. Setting and mechanical characteristics allow this class of castable and gun mixes to be placed more rapidly into service since the time required for curing is much less. Although initial set strengths are nct as high as those of conventional castables, very high strengths can be made to occur shortly after setting by heating. The addition of sodium hexametaphosphate was found to be highly beneficial to working and handling characteristics.</p> |