Corrosion Tests for Refractory Materials Intended for the Steel Industry - A Review

Abstract

The steel industry is one the biggest consumers of refractories. In this industry, refractories are commonly used as linings for steel production equipment, because they can sustain high temperature and corrosive attack in their working environment. However due to the harsh conditions, their life span is limited. Corrosion mainly by slag and molten steel is the principal phenomenon responsible for degradation and wear of the refractory bricks. It is a complex phenomenon that is due to infiltration (penetration) into and subsequent dissolution of the refractories by slags and molten steel. A thorough understanding of these mechanisms is necessary in order to improve the refractories behavior for steel making applications. However, even nowadays, no laboratory test can reproduce the real working conditions in the steel industry. According to the parameter of interest several testing methods have been developed. They can be static like the sessile drop test or crucible test or dynamic like the rotary slag test. This paper describes the principal corrosion tests used in the steel industry in order to give an overview of the way to determine and finally alleviate the impact of corrosion on refractories. Corrosion tests for refractory materials intended for the steel industry -A reviewCeramics - Silikáty 64 (3) 278-288 (2020)

Basic slag corrosion of alumina–magnesia–carbon refractory bricks containing Al and Si antioxidants

“…This characteristic was also observed in the cross‐section (Figure 1C), where discoloration was not evident. A neck was observed in the three‐way contact among air, slag, and refractory, where the wear was higher due to the Marangoni effect 16,8 . The superficial decarburization caused by the surrounding atmosphere is observed along the entire rod, although the upper part was less decarburized due to the low temperature there.…”

“…The rod thickness at the beginning and the end of the test (initial size and final size in Equation (1), respectively) is commonly used for the calculation. 16 The residual slag that adhered to the refractory rod, however, can alter the final thickness and, consequently, the calculated wear. To avoid this methodological error, the cross-section of the rods was used.…”

Nanocarbon containing low carbon Al 2 O 3 –C refractories: Comparison between N220 and N990 nanocarbons

“…Owing to its non-wetting nature graphite avoids the adhesion of slag on the refractory, thereby improving corrosion resistance. 6,16,[42][43][44][45] Sharp differences between the refractory and slag zones are visible in the micrograph of 3G 1NC provided in Figure 31. At the interface, a combination of alumina aggregates and flakes of graphite are present.…”

Corrosion of Alumina-Spinel Refractory by Secondary Metallurgical Slag Using Coating Corrosion Test

“…The impregnation of a refractory by liquid slag can be limited by reduction of pore size in the refractory, or increasing the slag viscosity. However, applying the specific solution to preserve the refractory lining against infiltration must respect factors required by the metallurgical process [ 3 , 7 , 8 , 9 ].…”

“…Lee and Zhang [ 10 ] studied the corrosion mechanism of oxide and oxide-carbon refractories through static corrosion methods, i.e., sessile drop, dipping, and crucible test, as well as dynamic techniques, like the rotating finger or slag rotary test [ 7 ]. Their studies showed that two main mechanisms govern the corrosion of refractory materials.…”