Tundish magnesium calcium ladle cover casting materials and preparation method thereof

Abstract

The invention relates to tundish magnesium calcium ladle cover casting materials. The tundish magnesium calcium ladle cover casting materials comprise the following components in percentage by weight:20-40wt% of magnesium sand granules, 20-40wt% of magnesium calcium sand granules, 5-15wt% of quick lime granules, 10-20wt% of a magnesium sand fine powder, 0.5-3wt% of an organic magnesium compound,1-6wt% of organic calcium, 2-6wt% of a thermoplastic micro powder, 2-8wt% of a magnesium oxide micro powder and 0.1-0.2wt% of a water reducing agent. The invention further relates to a method for preparing the tundish magnesium calcium ladle cover casting materials. According to the tundish magnesium calcium ladle cover casting materials and the preparation method thereof disclosed by the invention, the heat shock stability of fireproof materials is improved, besides, dissipation of heat quantity is effectively reduced, and favorable heat preservation properties and favorable thermal shock resistance of the materials are guaranteed; and when the tundish magnesium calcium ladle cover casting materials are applied to high-quality steel continuous casting tundishes, the temperature of a housing of a tundish ladle cover can be reduced by 10% or above averagely, and the average service life reaches 15 times or above.

Description

technical field [0001] The invention belongs to the technical field of refractory materials for tundishes, and in particular relates to a tundish magnesium-calcium covering castable with excellent thermal shock resistance and heat preservation performance and purified molten steel and a preparation method thereof. Background technique [0002] In recent years, with the enhancement of the metallurgical function of the tundish and the demand for energy saving and consumption reduction, the role of the cover of the continuous casting tundish has become more and more prominent. The quality of its use directly affects the output and quality of continuous casting steel. The function of the cover is mainly reflected in: it plays the role of heat preservation and heat insulation during the baking and pouring process of the tundish, improves the baking efficiency of the tundish and reduces the heat dissipation of the molten steel; thus protects the ladle slide mechanism from the direc...

AI Technical Summary

Problems solved by technology

Research and analysis found that the integrally welded steel structure undergoes large deformation with drastic temperature changes, and the difference in expansion coefficient between the steel structure and the refractory material prevents the refractory material from being in close contact with the steel structure for a long time, and the refractory material is easy to crack and peel off, resulting in steel The structure was burned, eventually leading to complete failure of the cladding

It can be seen that the poor service thermal shock resistance of the cover refractory is the main reason for the damage of the tundish cover, and a tundish cover castable and its preparation method (ZL201410242492.5) invented in the early stage can better solve the problem of thermal shock stability. However, the introduction of carbon can easily cause contamination of molten steel and the thermal conductivity is still relatively high, which needs to be solved urgently