First Hydrogenation of TiFe with Addition of 20 wt.% Ti
In this paper, we report the first hydrogenation (activation) of a 1.2Ti-0.8Fe alloy synthesized by induction melting (9 kg ingot). The alloy presented a three-phase structure composed of a main TiFe phase, a secondary Ti<sub>2</sub>Fe phase and a Ti-rich BCC phase. The alloy required co...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-09-01
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| Series: | Hydrogen |
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| Online Access: | https://www.mdpi.com/2673-4141/3/4/23 |
| _version_ | 1827638471138738176 |
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| author | Elena Ulate-Kolitsky Bernard Tougas Jacques Huot |
| author_facet | Elena Ulate-Kolitsky Bernard Tougas Jacques Huot |
| author_sort | Elena Ulate-Kolitsky |
| collection | DOAJ |
| description | In this paper, we report the first hydrogenation (activation) of a 1.2Ti-0.8Fe alloy synthesized by induction melting (9 kg ingot). The alloy presented a three-phase structure composed of a main TiFe phase, a secondary Ti<sub>2</sub>Fe phase and a Ti-rich BCC phase. The alloy required cold rolling to achieve activation at room temperature. However, it did so with good kinetics, reaching saturation (2.6 wt.% H) in about 6 h. After activation, the phases identified were TiFe, Ti<sub>2</sub>FeH<sub>x</sub> and an FCC phase. The Ti<sub>2</sub>FeH<sub>x</sub> and FCC are the stable hydrides formed by the secondary Ti<sub>2</sub>Fe and BCC phases, respectively. The stoichiometry of the Ti<sub>2</sub>FeH<sub>x</sub> was calculated to be between x = 3.2–4.75. As the microstructure obtained by an industrial-scale synthesis method (induction melting) may be different than the one obtained by laboratory-scale method (arc melting), a small 3 g sample of Ti<sub>1.2</sub>Fe<sub>0.8</sub> was synthesized by arc melting. The lab-scale sample activated (2 wt.% H in ~12 h) without the need for cold rolling. The phases identified for the lab-scale sample matched those found for the induction-melted sample. The phase fractions differed between the samples; the lab-scale sample presented a lower abundance and a finer distribution of the secondary phases. This explains the difference in the kinetics and H capacity. Based on these results it can be concluded that the alloy of composition, 1.2Ti-0.8Fe, can absorb hydrogen without the need for a heat treatment, and that finer microstructures have a strong influence on the activation kinetics regardless of the secondary phases’ phase fractions. |
| first_indexed | 2024-03-09T16:20:44Z |
| format | Article |
| id | doaj.art-789b448925294c53a2d05d216faa14f8 |
| institution | Directory Open Access Journal |
| issn | 2673-4141 |
| language | English |
| last_indexed | 2024-03-09T16:20:44Z |
| publishDate | 2022-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Hydrogen |
| spelling | doaj.art-789b448925294c53a2d05d216faa14f82023-11-24T15:17:23ZengMDPI AGHydrogen2673-41412022-09-013437938810.3390/hydrogen3040023First Hydrogenation of TiFe with Addition of 20 wt.% TiElena Ulate-Kolitsky0Bernard Tougas1Jacques Huot2Centre de Métallurgie du Québec, Trois-Rivières, QC G9A 5E1, CanadaCentre de Métallurgie du Québec, Trois-Rivières, QC G9A 5E1, CanadaHydrogen Research Institute, Université du Québec à Trois-Rivières, Trois-Rivières, QC G8Z 4M3, CanadaIn this paper, we report the first hydrogenation (activation) of a 1.2Ti-0.8Fe alloy synthesized by induction melting (9 kg ingot). The alloy presented a three-phase structure composed of a main TiFe phase, a secondary Ti<sub>2</sub>Fe phase and a Ti-rich BCC phase. The alloy required cold rolling to achieve activation at room temperature. However, it did so with good kinetics, reaching saturation (2.6 wt.% H) in about 6 h. After activation, the phases identified were TiFe, Ti<sub>2</sub>FeH<sub>x</sub> and an FCC phase. The Ti<sub>2</sub>FeH<sub>x</sub> and FCC are the stable hydrides formed by the secondary Ti<sub>2</sub>Fe and BCC phases, respectively. The stoichiometry of the Ti<sub>2</sub>FeH<sub>x</sub> was calculated to be between x = 3.2–4.75. As the microstructure obtained by an industrial-scale synthesis method (induction melting) may be different than the one obtained by laboratory-scale method (arc melting), a small 3 g sample of Ti<sub>1.2</sub>Fe<sub>0.8</sub> was synthesized by arc melting. The lab-scale sample activated (2 wt.% H in ~12 h) without the need for cold rolling. The phases identified for the lab-scale sample matched those found for the induction-melted sample. The phase fractions differed between the samples; the lab-scale sample presented a lower abundance and a finer distribution of the secondary phases. This explains the difference in the kinetics and H capacity. Based on these results it can be concluded that the alloy of composition, 1.2Ti-0.8Fe, can absorb hydrogen without the need for a heat treatment, and that finer microstructures have a strong influence on the activation kinetics regardless of the secondary phases’ phase fractions.https://www.mdpi.com/2673-4141/3/4/23TiFeoverstoichiometryactivation kineticsTi<sub>2</sub>Festable hydrides |
| spellingShingle | Elena Ulate-Kolitsky Bernard Tougas Jacques Huot First Hydrogenation of TiFe with Addition of 20 wt.% Ti Hydrogen TiFe overstoichiometry activation kinetics Ti<sub>2</sub>Fe stable hydrides |
| title | First Hydrogenation of TiFe with Addition of 20 wt.% Ti |
| title_full | First Hydrogenation of TiFe with Addition of 20 wt.% Ti |
| title_fullStr | First Hydrogenation of TiFe with Addition of 20 wt.% Ti |
| title_full_unstemmed | First Hydrogenation of TiFe with Addition of 20 wt.% Ti |
| title_short | First Hydrogenation of TiFe with Addition of 20 wt.% Ti |
| title_sort | first hydrogenation of tife with addition of 20 wt ti |
| topic | TiFe overstoichiometry activation kinetics Ti<sub>2</sub>Fe stable hydrides |
| url | https://www.mdpi.com/2673-4141/3/4/23 |
| work_keys_str_mv | AT elenaulatekolitsky firsthydrogenationoftifewithadditionof20wtti AT bernardtougas firsthydrogenationoftifewithadditionof20wtti AT jacqueshuot firsthydrogenationoftifewithadditionof20wtti |