Aluminum oxide-silicon carbide-carbon castable with high hot strength

Abstract

The invention relates to an aluminum oxide-silicon carbide-carbon castable with high hot strength. According to a technical scheme, the aluminum oxide-silicon carbide-carbon castable comprises the following components in percentage by weight: 58-62 wt% of compact corundum aggregate, 6-10 wt% of silicon carbide particles, 2-3 wt% of spherical asphalt, 4-10 wt% of aluminum oxide micro-powder, 4-5 wt% of silicon dioxide micro-powder, 7-10 wt% of silicon carbide powder, 1 to 1.5 wt% of silicon powder, 6-9 wt% of fine compact corundum powder and 0.1-0.2 wt% of polyacrylic acid. A preparation methodfor the castable comprises the following steps: subjecting the above components to burdening and mixing according to the respective contents; and adding water accounting for 3-3.3 wt% of the total mass of the components, performing uniform stirring, carrying out vibration molding, conducting natural drying for 24 hours, and carrying out heat treatment at 110 DEG C for 24 hours to obtain the aluminum oxide-silicon carbide-carbon castable with high hot strength. The castable has the characteristics of high hot strength, high density and good volume stability.

Description

technical field [0001] The invention belongs to the technical field of alumina-silicon carbide-carbon castable. Specifically relates to an aluminum oxide-silicon carbide-carbon castable with high thermal strength. Background technique [0002] At present, most domestic blast furnace casting plants use alumina-silicon carbide-carbon refractory castables, which are mainly used in the iron trough of the casting plant. During the operation of the iron trough, it has been strongly eroded and corroded by molten iron and slag above 1450°C for a long time. The service environment of the iron trough castable is extremely harsh, and the thermal strength is the most reflective of the alumina-silicon carbide-carbon castable. An important indicator of the material's application performance under such high-temperature scour. [0003] The bonding performance of the iron channel castable directly affects the hot strength of the material. For the research on the bonding system of iron tro...

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Problems solved by technology

However, due to its own insurmountable shortcomings (such as poor construction performance, freezing failure in winter, high water content, etc.), the use effect of silica sol has no significant advantages compared with cement-bonded iron trough castables, and it has no significant effect on the thermal state of iron trough castables. The increase in strength is not obvious

Hydraulic alumina is used as a binding agent to replace cement in iron trench castables. Not only the bonding strength is low, but also the stability of hydraulic alumina is poor, especially the hydration rate is extremely sensitive to the influence of external temperature fluctuations. The process of losing crystal water under high temperature conditions (800-1100°C) will produce a large number of microcracks, which will reduce the density of the structure of the material.

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