Effect of Pore Formation in Sintered Ore under H2–CO–N2 Atmosphere on Reduction Disintegration
Year: 2026
Type: article
Abstract: Reducing CO2 emissions is crucial for the steel industry. The use of hydrogen in blast furnaces has attracted attention as a promising alternative to fossil fuels and a means to reduce CO2 emissions. However, the reduction disintegration behavior of sintered ores under hydrogen-rich atmospheres remains unclear. In this study, reduction disintegration tests were conducted at 550 °C in H2–CO–N2 atmospheres. The results showed that the reduction disintegration index (RDI) increased in H2–CO–N2 atmospheres compared with CO–N2 atmospheres, owing to the faster reduction of hematite in the presence of hydrogen. Microstructural analysis using scanning electron microscopy (SEM) and mercury porosimetry indicated that reduction induced the formation of micropores (0.0036–0.2 µm) and cracks (0.2–10 µm). Micropores formed in grains where hematite was reduced to magnetite, whereas cracks were mainly observed at interfaces where iron oxides coexisted with other phases. Quantitative analysis revealed a strong correlation between crack formation and the RDI. Comparison of the reduction disintegration behavior of sintered ores under H2–CO–N2 and CO–N2 atmospheres at the same reduction degree revealed that effects of gas composition and hydrogen concentration were minor, indicating that the reduction of hematite was the dominant factor.
Source: 鐵と鋼 : 日本鐡鋼協會々誌
Institution: JFE Steel Corporation (Japan)
Language: English
Subfield: Metals and Alloys
Field: Materials Science
Domain: Physical Sciences
SDG: Climate action
Open Access status: diamond
OpenAlex ID: W7214955849