The powder of hematite sample was isothermally reduced with hydrogen-water vapor gas mixture at 1023K-1273K. The results indicated that the overall reduction process of hematite could be separated into three stages (Fe2O3-Fe3O4-FeO-Fe) to respectively study. At 1023K, the average reaction rate dropped by 53.6% in the stage 1 when the water vapor content of gas reactant rose from 0% to 50%, and it decreased by about 77.2% in the stage 2. However, in the stage 3, when the water vapor content only increased from 0% to 20%, it decreased by about 78.1%. Besides, the average reaction rate had a roughly negative linear relationship with the water vapor content, and the results further shown that the effect of water vapor on the reduction reaction increased with increasing reaction temperature at all stages of the reduction reaction. The microstructure of reduction products showed that it still had some holes, which the channel for hydrogen diffusion was not seriously blocked. In order to further clarify the influence of water vapor in the reduction stage, different models were considered, and the range of apparent activation energy of different stages obtained by model fitting was about 20-70 kJ/mol, which also confirmed the absence of solid-state diffusion phenomenon.

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The erosion experiments of Al–Li melt on 316L stainless steel were carried out at different temperatures and holding times. In this study, the microstructure and composition of an Al–Li/316L liquid–solid interface was analyzed by inductively coupled plasma atomic emission spectroscope (ICP-AES), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). The phase transformation and structure evolution of the erosion process were studied to explain the erosion mechanism and kinetics. The results showed that Fe/Cr/Ni–Al intermetallic compounds (IMC) were formed at the Al–Li/316L interface, and the diffusion of Cr atoms lead to the accumulation of Ti in the Al–Li melt, to form TiAl3 and CrAl4. With the increase in temperature and holding time, the thickness of the Fe-containing erosion layer (EL) increased, and the morphology of Ti-containing erosion particles (EP) became larger and more regular. The apparent activation energy (Ea) of the Fe-containing erosion layer was 124.82 kJ·mol−1. Meanwhile, a kinetics equation for predicting the service life of 316L was obtained. The research results provided a theoretical guidance for the smelting and casting of an Al–Li alloy.

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