Deoxidation of Titanium Using Ytterbium-Halide-Flux Method

Efficient removal of oxygen (O) impurities from titanium (Ti) scrap is necessary to accelerate the recycling of Ti scrap. However, deoxidation of Ti is extremely difficult, both thermodynamically and technically. In this study, we developed a deoxidation technique that uses Yb (a rare earth metal wi...

Full description

Saved in:
Bibliographic Details
Main Authors: Takanari OUCHI, Kenta AKAISHI, Gen KAMIMURA, Toru H. OKABE
Format: Article
Language:English
Published: The Mining and Materials Processing Institute of Japan 2024-11-01
Series:Journal of MMIJ
Subjects:
Online Access:https://www.jstage.jst.go.jp/article/journalofmmij/140/11/140_2024-007/_pdf/-char/en
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850263479691247616
author Takanari OUCHI
Kenta AKAISHI
Gen KAMIMURA
Toru H. OKABE
author_facet Takanari OUCHI
Kenta AKAISHI
Gen KAMIMURA
Toru H. OKABE
author_sort Takanari OUCHI
collection DOAJ
description Efficient removal of oxygen (O) impurities from titanium (Ti) scrap is necessary to accelerate the recycling of Ti scrap. However, deoxidation of Ti is extremely difficult, both thermodynamically and technically. In this study, we developed a deoxidation technique that uses Yb (a rare earth metal with high vapor pressure at elevated temperatures) to directly remove O dissolved in solid Ti. Experimental results showed that deoxidation using Yb in halide salt fluxes such as LiCl and LiF produced Ti with O concentrations of 520-1400 mass ppm. The O concentration in deoxidized Ti samples was reduced to a level lower than that in Ti under the Yb/Yb2O3 equilibrium, probably owing to the decrease in the activity of Yb2O3, which was the deoxidation product, caused by its dissolution in the fluxes. In contrast, when vapor of Yb metal and halide salts were supplied to Ti samples via a gas phase, the Ti samples were deoxidized to the same O concentration as that under the Yb/Yb2O3 equilibrium. This deoxidation limit was controlled by the Yb/Yb2O3 equilibrium. The supply of halide salt vapor did not affect the deoxidation limit. The proposed deoxidation method is expected to help scale up the recycling of Ti scrap and ensure efficient utilization of resources.
format Article
id doaj-art-f15bbec0c1904bc1992a4e11a99263f3
institution OA Journals
issn 1881-6118
1884-0450
language English
publishDate 2024-11-01
publisher The Mining and Materials Processing Institute of Japan
record_format Article
series Journal of MMIJ
spelling doaj-art-f15bbec0c1904bc1992a4e11a99263f32025-08-20T01:54:57ZengThe Mining and Materials Processing Institute of JapanJournal of MMIJ1881-61181884-04502024-11-011401115716910.2473/journalofmmij.MMIJ-2024-007journalofmmijDeoxidation of Titanium Using Ytterbium-Halide-Flux MethodTakanari OUCHI0Kenta AKAISHI1Gen KAMIMURA2Toru H. OKABE3Institute of Industrial Science, The University of TokyoInstitute of Industrial Science, The University of Tokyo / Department of Materials Engineering, Graduate School of Engineering, The University of TokyoInstitute of Industrial Science, The University of TokyoInstitute of Industrial Science, The University of TokyoEfficient removal of oxygen (O) impurities from titanium (Ti) scrap is necessary to accelerate the recycling of Ti scrap. However, deoxidation of Ti is extremely difficult, both thermodynamically and technically. In this study, we developed a deoxidation technique that uses Yb (a rare earth metal with high vapor pressure at elevated temperatures) to directly remove O dissolved in solid Ti. Experimental results showed that deoxidation using Yb in halide salt fluxes such as LiCl and LiF produced Ti with O concentrations of 520-1400 mass ppm. The O concentration in deoxidized Ti samples was reduced to a level lower than that in Ti under the Yb/Yb2O3 equilibrium, probably owing to the decrease in the activity of Yb2O3, which was the deoxidation product, caused by its dissolution in the fluxes. In contrast, when vapor of Yb metal and halide salts were supplied to Ti samples via a gas phase, the Ti samples were deoxidized to the same O concentration as that under the Yb/Yb2O3 equilibrium. This deoxidation limit was controlled by the Yb/Yb2O3 equilibrium. The supply of halide salt vapor did not affect the deoxidation limit. The proposed deoxidation method is expected to help scale up the recycling of Ti scrap and ensure efficient utilization of resources.https://www.jstage.jst.go.jp/article/journalofmmij/140/11/140_2024-007/_pdf/-char/endeoxidationtitanium scraprecyclingytterbium
spellingShingle Takanari OUCHI
Kenta AKAISHI
Gen KAMIMURA
Toru H. OKABE
Deoxidation of Titanium Using Ytterbium-Halide-Flux Method
Journal of MMIJ
deoxidation
titanium scrap
recycling
ytterbium
title Deoxidation of Titanium Using Ytterbium-Halide-Flux Method
title_full Deoxidation of Titanium Using Ytterbium-Halide-Flux Method
title_fullStr Deoxidation of Titanium Using Ytterbium-Halide-Flux Method
title_full_unstemmed Deoxidation of Titanium Using Ytterbium-Halide-Flux Method
title_short Deoxidation of Titanium Using Ytterbium-Halide-Flux Method
title_sort deoxidation of titanium using ytterbium halide flux method
topic deoxidation
titanium scrap
recycling
ytterbium
url https://www.jstage.jst.go.jp/article/journalofmmij/140/11/140_2024-007/_pdf/-char/en
work_keys_str_mv AT takanariouchi deoxidationoftitaniumusingytterbiumhalidefluxmethod
AT kentaakaishi deoxidationoftitaniumusingytterbiumhalidefluxmethod
AT genkamimura deoxidationoftitaniumusingytterbiumhalidefluxmethod
AT toruhokabe deoxidationoftitaniumusingytterbiumhalidefluxmethod