Central Band Structures: New Insights into the Coupling Effects Between the Pores and Minerals of Sinter
- PDF / 6,667,840 Bytes
- 10 Pages / 593.972 x 792 pts Page_size
- 15 Downloads / 180 Views
tering is a traditional method used to prepare functional materials, which has been widely used in the fields of ceramics, metallurgy, refractory materials, and ultrahigh-temperature materials.[1–3] With regard to the steel industry, sinter is an essential, iron-containing raw material that is used in the blast furnace. China produces 1100 million tons of sinter per annum.[4] Unlike solid-state sintering, iron-ore sintering is a very complicated process because of the presence of coke and flux within the raw materials. Iron-ore sintering involves a series of physicochemical reactions, such as fuel combustion, liquid-phase formation, liquid-phase crystallization, and solid-phase consolidation.[5,6] For many years, to improve the quality of sinter, many researchers have investigated the phase evolution that occurs during sintering. It is apparent that a suitable mineralogical structure is key for the production of high-quality sinter. In addition, the microstructures of sinters are
JIANLIANG ZHANG, ZHENGJIAN LIU, YAOZU WANG, CHENGBO DU, and LELE NIU are with school of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, 30th Xueyuan Road, Haidian district, Beijing 100083, P.R. China. Contact e-mail: [email protected] Manuscript submitted August 20, 2018. METALLURGICAL AND MATERIALS TRANSACTIONS B
determined by their mineral composition and pore structure.[7–9] Researchers have elucidated the relationship between the mineral compositions of sinter and their performances, and have gradually developed the iron-ore sintering theory based on the silico-ferrite of calcium and aluminum (SFCA).[10,11] Several researchers[12–14] have shown that the pore structure of a sinter has a significant influence on its strength and metallurgical performance. The pores within the sinter will accelerate reduction by increasing both the diffusion path of the reducing gas and the specific surface area of the sinter.[15–17] However, cracks are likely to form around pores, which may weaken the tumbler strength and lower the temperature reduction degradation index (RDI) of the sinter.[18] Many studies have focused on the minerals present within sinters; however, these studies have primarily focused on the relationship between the mineral compositions of the sinters and their performances. However, the pore structures, especially the coupling effects that exist between the pores and minerals of the sinter, have often been overlooked. In this study, four types of central band structures (CBSs) were defined to represent the coupling effects that exist between the pores and minerals of the sinter. Extensive research on the mineralogical structures of various types of sinter (low-SiO2 sinter, medium-SiO2 sinter, high-SiO2 sinter, and TiO2-containing sinter) was conducted to classify various types of CBS and determine their formation mechanisms. The cracking behavior of each CBS was investigated by performing a series of reduction experiments at a temperature of 873 K. This study aims to investigate the coupling effe
Data Loading...
