High-temperature antioxidizing paint for lowering oxidation burning of steel in heating furnace

Abstract

The invention relates to a high temperature anti-oxidation coating capable of reducing the oxidation burning loss of stainless steel in a heating furnace. The high temperature anti-oxidation coating is characterized in that the coating comprises solid materials consisting of 46 to 92 percent of basic filler and 8 to 54 percent of composite binder, and water which is 0.5 to 20 folds of the weight of the solid materials. The basic filler comprises several chemical components selected from silicon dioxide, alumina, magnesia, calcium oxide and boric oxide. The composite binder consists of severalcomponents selected from sodium silicate, lithium metasilicate and aluminum phosphate. The coating can be painted at the normal temperature or sprayed onto the surface of a stainless steel billet from the room temperature to 1,000 DEG C. The coating can form a protective coat at the high temperature, thereby greatly reducing the high temperature oxidation burning loss of stainless steel at 1,400 DEG C, and reducing the unit area oxidation burning loss by more than 90 percent. After stainless steel is drawn out of the furnace, the iron oxide scale can be fully stripped off under the actions oftemperature reduction or high pressure water; the amount of the produced iron oxide scale is also obviously reduced; and the stainless steel surface quality is remarkably improved.

Description

technical field [0001] The invention belongs to the field of coatings, in particular to a high-temperature anti-oxidation coating for reducing oxidation and burning loss of stainless steel in a heating furnace. Background technique [0002] The heating of stainless steel billets before hot rolling is an essential and important process in the production of stainless steel. Among them, the environment in the heating furnace is extremely harsh, the furnace gas temperature is as high as 1200°C-1350°C, and the instantaneous impact temperature can reach 1450°C. And the furnace gas contains H 2 O.CO 2 , O 2 and other oxidizing components. This environment causes severe oxidation of the stainless steel billet, resulting in oxidation and burning of the metal. High-temperature oxidation will also cause the depletion of alloy elements on the surface of stainless steel, and at the same time generate a dense spinel structure oxide scale that is closely combined with the surface of s...

AI Technical Summary

Problems solved by technology

According to patent documents, "a nano-silicate anti-oxidation coating for series steel billet annealing" (application number 200710053874.3) is cured by weight percentage of 20-30% binder and 8-12% composite phosphate 58-72% composite aluminosilicate filler, which can reduce the oxidation and burning loss of austenitic stainless steel 0Cr18Ni9, but the high alumina powder and zirconia in the raw materials need to be nano-sized, which undoubtedly increases the coating cost; and The paint is directly sprayed on the steel billet to cure in ten minutes, which is inconsistent with the development status of the stainless steel continuous casting and rolling-hot billet into the furnace, which limits the popularization and application