Abstract:Calcium ferrite containing aluminum (CFA) is an important precursor compounds in the formation of silico-ferrite of calcium and aluminum (SFCA). In order to reveal the formation behavior and reaction mechanism of CFA,the samples of sinter were prepared by adopting the method of briquetting-sintering,then XRD and SEM-EDS were used to investigate the mineral formation and element migration in the CaO-Al2O3-Fe2O3system at different sintering temperatures. The results show that CFA was generated through three-stage reaction. Firstly,dicalcium ferrite (C2F) was formed at low sintering temperature (<750 ℃),and then with the sintering temperature rising to 800-950 ℃,C2F reacts with Fe2O3 to generate calcium ferrite (CF). Secondly,Al2O3 reacts with CaO to generate semi-calcium aluminate (CA2) after the sintering temperature rises to 900-950 ℃,and then CFA was generated at the ternary interface of CF-CA2-Fe2O3. Finally,the acicular CFA product layer was formed around CA2.
胡长庆, 韩涛, 师学峰. 含铝铁酸钙CFA的生成行为[J]. 钢铁, 2020, 55(8): 70-74.
HU Chang-qing, HAN Tao, SHI Xue-feng. Formation behavior of calcium ferrite containing aluminum[J]. Iron and Steel, 2020, 55(8): 70-74.
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