A kind of high temperature resistant release coating and preparation method thereof

Abstract

The invention discloses high temperature-resistant de-molding paint which is prepared from alkaline silica sol, graphite powder and a dispersing agent in a proportion of 100:(5-20):(0.1-1), wherein SiO2 content of the alkaline silica sol is 20%-40%; and grain size of the graphite powder is 30 meshes-100 meshes. According to the high temperature-resistant de-molding paint as well as the preparation method disclosed by the invention, conglutination of the paint can be greatly lowered by adding the graphite powder in the alkaline silica sol, a paint protective layer obtained by coating is uniform in thickness, flat and smooth, and bottom and sides are protected; moreover, dosage is a little, and a firm protective film can be formed by only spraying a thin layer of paint; besides, the graphite powder and the silica sol are uniformly fixed, and after forming the protective layer, the graphite powder is dispersed in the silica sol and not dispersed inside a cast ingot to affect product quality.

Description

technical field [0001] The invention relates to a high-temperature-resistant coating, in particular to a coating capable of protecting an ingot mold from being eroded by high-temperature erosion. Background technique [0002] High-temperature coatings generally refer to special functional coatings that can withstand temperatures above 200°C for a long time, and can maintain certain physical and chemical properties, so that the protected objects can function normally in high-temperature environments. As a protective material, coating is widely used in machinery, electronics, aerospace, chemical industry, construction and other fields. [0003] With the expansion of the coating field, some conventional coatings gradually cannot meet the new application requirements, including the temperature resistance of the coating. Most of the coatings we use are organic coatings, and their use temperature is mostly limited to a slightly higher temperature, generally not exceeding 250 °C. ...

AI Technical Summary

Problems solved by technology

But it has many disadvantages: ①The thickness of the graphite powder layer is uneven, and it is difficult to form a protection on the side of the ingot mold; ②The graphite powder layer is too thin to effectively protect the ingot mold, and the amount of graphite powder is too thick. Large, high cost; ③The graphite powder is not bonded to the ingot mold, and the scouring force formed when the high-temperature liquid starts pouring can easily wash away the graphite powder, thereby damaging the ingot mold; ④The density of graphite powder is small, and the density of ferroalloy liquid / silicon liquid Large, part of the graphite powder will float and diffuse into the liquid, and stay in the ingot after cooling, increasing the content of impurity carbon; After the smelting liquid in the ingot mold is cooled, the silicon block / powder will be fused together, which brings more impurities into the smelting liquid, and because a part of the silicon needs to be used as an interlayer, the use efficiency of the ingot mold is reduced