中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 31 No. 10 October 2021 |
（1. Instrumental Analysis Center, Inner Mongolia University of Science and Technology, Baotou 014010, China;
2. Department of Functional Material Research, Central Iron and Steel Research Institute, Beijing 100081, China）
Abstract:The as-spun Ti1-xLaxFe0.8Mn0.2 (x=0, 0.01, 0.03, 0.06, 0.09, molar fraction) alloys were prepared by melt spinning. The effects of La substitution for Ti on the microstructure, hydrogen storage kinetics and thermodynamics of TiFe-type Ti-Fe-Mn-based alloy were investigated. The as-spun alloys hold the TiFe single phase, which transforms to TiFeH0.06, TiFeH, and TiFeH2 hydrides after hydrogenation. La substitution promotes the formation of micro-defects (such as dislocations and grain boundaries) in the alloys, thus facilitating hydrogen diffusion. In addition, the hydrogen storage kinetics properties are improved after introducing La element. With the rise of La content, the hydrogen storage capacity decreases firstly and then increases, but the absolute value of hydriding enthalpy change (|ΔH|) increases firstly and then reduces. When x=0.01, the maximum value of |ΔH| is obtained to be (25.23±0.50) kJ/mol for hydriding, and the alloy has the maximum hydrogen absorption capacity of (1.80±0.04) wt.% under the conditions of 323 K and 3 MPa.
Key words: La substitution; Ti-Fe-Mn-based alloy; melt spinning; hydrogen storage kinetics; thermodynamics
