What are the measures to improve the quality of castables
(1) The raw materials with high purity, few impurities and good high-temperature volume stability can be used to improve the high-temperature volume stability and erosion resistance of the castable.
(2) Minimize the amount of CaO, that is, minimize the amount of cement, because the increase in CaO content will greatly increase the number of liquid phases; this is not good for the high temperature performance of the castable.
(3) Add appropriate amount of a-Al2O3 to increase the medium temperature strength of the material, because a-Al2O3 can react with CaO to form CA and CA2, which results in a certain volume expansion. This expansion effect can make up for the castable due to dehydration and crystal form conversion The volume shrinks.
(4) Add an appropriate amount of soft clay as a sintering agent, and promote the formation of liquid phase and sintering to form a ceramic bond.
(5) A certain amount of expansion agent (kyanite) is added to expand the volume formed by mullite formation of the kyanite material to improve the volume shrinkage of the material during the sintering process.
(6) The addition of heat-resistant stainless steel fibers improves the thermal shock resistance of the material and enhances the toughness of the material, which can reduce the structural spalling and damage of the castable.
(7) Add an appropriate amount of anti-explosion agent to facilitate the smooth discharge of water vapor in the castable during baking to improve the baking quality of the castable.