Fireproof material for steel ladle bottom and preparation method thereof

Abstract

The invention discloses a fireproof material for a steel ladle bottom. The fireproof material is made of a framework and castable. The framework is made of large clinkers of which granularity ranges from 50mm to 400m, and the castable is made of aluminum-magnesium auto-flowing castable in which rho-aluminum oxide is used as a binding agent. According to the fireproof material, the large clinkers which are well sintered and are compact in structure are used as the ladle bottom refractory framework, and therefore molten steel washing resistance of the framework is effectively enhanced; the aluminum-magnesium auto-flowing castable in which rho-aluminum oxide is used as the binding agent belongs to non-cement castable, and the castable has the advantages that an integrative system is pure and liquid phase amount generated under high temperature is small; the aluminum-magnesium auto-flowing castable generates spinels in situ under the high temperature condition, the in-situ generated spinels are used as a binder phase, and then the castable has the advantages of being good in thermal shock stability performance and not prone to peeling in the using process, the castable and the framework are encapsulated and poured into a whole, and therefore the fireproof material has the advantages of being high in molten steel washing resistance, good in peeling resistance, long in service life and the like. The fireproof material can have the good using effect in various steel ladle bottoms.

Description

technical field [0001] The invention relates to an unshaped refractory material, in particular to a refractory material for the bottom of a ladle and a preparation method thereof. Background technique [0002] During use, the ladle bottom refractory material not only bears the thermal shock damage caused by the erosion of molten steel and temperature changes, but also infiltrates and over-sinters under the huge pressure of molten steel, resulting in structural spalling, which makes the ladle bottom refractory damage much faster In the ladle wall and slag line, this has become a key factor restricting the service life of the ladle, and it also brings hidden dangers to safe production. Therefore, improving the quality of the ladle bottom refractory material and improving the masonry method have become the focus of technical workers' research. The existing ladle bottom refractory materials are generally formed by pouring castables or by masonry with refractory bricks. The pub...

AI Technical Summary

Problems solved by technology

The publication number is CN1680059A, which discloses "a large-scale ladle bottom refractory material", which uses 70-85wt% of special-grade bauxite with a particle size of less than 15mm, 3-15wt% of magnesia fine powder, and 3-10wt% of magnesium-aluminum spinel powder. , silicon micropowder 0.5~5wt%, magnesium binder 1~5%, and dispersant 0.1~0.2%, by reducing the load softening temperature of the material and controlling the appropriate thermal expansion rate and other technical measures to improve the use effect; but the load The reduction of softening temperature means that the high-temperature strength of the material is reduced, which leads to the reduction of high-temperature erosion resistance; the publication number is CN1546258A, which discloses a "micro-expansion self-flowing castable for the bottom of the ladle", which is 0-15% sharp spar, 0-10% magnesia, 0-8% pure calcium aluminate cement, 0.5-5% silicon micropowder, 6-10% α-alumina micropowder as matrix, high alumina bauxite as aggregate, through Adjust the content of magnesia, spinel and silica powder in the formula, adjust the linear change rate and sintering of the material to improve the performance of the material; but the phase composition of the castable is complex, and the CaO-Al2O3-MgO-SiO2 system is used There are more low-melting materials in the process, resulting in poor erosion resistance and erosion resistance of the material during use