Study of the addition of a chemical mix additive and curing temperature on the setting time and mechanical properties of no‐cement castable

Abstract

AbstractTight installation schedules and economic pressures are potential drawbacks for castable installation and performance. Many factors influence the setting behavior and the properties of no‐cement castable refractories, including temperature and chemical composition. In this study, the setting behavior and the mechanical properties of a no‐cement castable were analyzed varying the amount of a chemical additive mix and curing temperature. The chemical additive mix concentration was varied from 0 wt% to 1 wt%. The curing temperature was varied from low (4°C/40°F) to high (40°C/104°F). The mechanical properties were characterized by cold crushing strength (CCS). A variance in the pH level drastically increased the setting time of the castable. Mechanical properties on green samples showed lower strength for castables with a higher concentration of the additive mix. This difference in performance is the result of the lower pH preventing the formation of a chain mechanism in the no‐cement castable bonded with colloidal silica.