Continuous casting slab high-temperature oxidation resistant coatings and preparation process thereof

Abstract

The invention relates to a preparation process of continuous casting slab high-temperature oxidation resistant coatings, which is characterized in that less than 120 meshes of powder, reductant containing carbon, inorganic binders, surfactants, suspending agents and the like with the compositions such as 25-55 wt% SiO2, 10-20 wt% Al203, 11-23 wt% MgO and the like are respectively grinded and mixed evenly, then water is used to be mixed and stirred sufficiently evenly, and finally the density of the coatings are adjusted within 1200-1500 kg / m3. The coatings can not only be sprayed onto continuous casting slabs at normal temperature, but also be sprayed onto high-temperature casting slabs, form continuous whole protective coating layers under the action of high temperature, effectively reduce temperature drop of the casting slabs and oxidation burning loss in even heating process of a heating furnace without changing original performance of matrixes, and effectively decrease dilution of alloying elements on the surfaces of the casting slabs. After the casting slabs are out of the heating furnace, natural spalling capability of the coating layers is strong, and oxidation matrixes of the casting slabs are smooth. Raw materials of the oxidation resistant coatings are easy to be obtained, and the coatings have low cost and simple preparation process and are adaptable to oxidation resistance for various steels when being heated at 700-1300 DEG C / 2-8 hours.

Description

technical field [0001] The invention belongs to the field of coatings, and in particular relates to high-temperature anti-oxidation coatings for continuous casting slabs and a preparation process thereof. Background technique [0002] Energy saving and emission reduction is the goal pursued by all industries in the world, especially for iron and steel enterprises with high energy consumption. The continuous casting slab needs to be heated in the heating furnace at a high temperature of about 1200°C and for a long time before hot rolling. This process makes the oxidative burning loss on the surface of the slab very serious, and the oxidation burning loss rate reaches 0.5-2.5%. In order to reduce the oxidative burning loss of the slab and reduce the surface temperature drop of the slab during transportation, an anti-oxidation coating is applied to the surface of the high-temperature slab to reduce the temperature drop of the slab and increase the yield and improve the steel qu...

AI Technical Summary

Problems solved by technology

Although this coating has certain high temperature resistance, oxidation resistance and thermal stability, the cost of the coating is too high, the process is complicated, the additives are too many, it is not easy to mix, and it is not suitable for industrial production and promotion.

[0006] Although the above-mentioned coatings have good high-temperature anti-oxidation effects on the specified billet to a certain extent, most of these coatings are limited to normal temperature coating, drying, film formation and static high-temperature protection, which limits the promotion of such achievements