Influence of FeO-TiO-MgO-Al2O3 Slag on Reducing Ti Loss and Removing Impurities in Fe-Ti Alloys Production Using Ti Turning Scrap

Yong-Woo Kim; Sun-Joong Kim

doi:10.7844/kirr.2025.34.4.40

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2025 Vol.34, Issue 4 Preview Page Next Page

Research Paper

Influence of FeO-TiO-MgO-Al₂O₃ Slag on Reducing Ti Loss and Removing Impurities in Fe-Ti Alloys Production Using Ti Turning Scrap Ti Turning Scrap 활용 Fe-Ti 합금 제조시 합금 내 Ti 손실 저감 및 불순물 제거에 미치는 FeO-TiO-MgO-Al₂O₃ 슬래그의 영향

31 August 2025. pp. 40-47

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Abstract

A large amount of scrap of Ti turnings is generated from manufacturing processes of sponge and product. One method of recycling of Ti scrap is through the production of ferrotitanium alloys. However, during the production of ferrotitanium alloys, impurities in Ti scrap can lead to an increase in the overall impurities and a loss of Ti from the Fe-Ti alloy. In the present study, the influence of the slag composition on reducing the loss of Ti and the removal of impurities from Fe-Ti alloys was investigated by evaluating the equilibrium between the FeO-TiO₂-MgO-Al₂O₃ multi-component slag and an Fe-Ti melt with a titanium content of over 60 wt% at 1873 K under Ar atmosphere. The Ti content in the Fe-Ti alloy was adjusted by charging with scrap of Ti turnings from industry. When the Fe-Ti alloy was melted with the addition of Al scrap, Ti loss from the Fe-Ti alloy decreased owing to the preferential oxidation of Al over Ti in the Fe-Ti melts and the reduction in the activity coefficient of TiO for the slag containing Al₂O₃. On the other hand, regardless of Al addition, the contents of N and C in the Fe-Ti alloy decreased

Keywords

Ferro-titanium

Equilibrium reaction

Ti turning scrap

Recycling

Ti 터닝 스크랩은 스펀지 제조 공정, 가공용 소재 제조 공정, 제품 제조 공정 등 다량으로 발생하고 있으며, 이러한 스크랩의 재활용 공정 중 하나는 Fe-Ti 합금 제조이다. 그러나 Fe-Ti 합금 제조 시 Ti 스크랩의 불순물로 인한 합금내 불순물 증가 및 합금 내 Ti 손실 등의 문제가 발생할 수 있다. 본 연구에서는 1873K 및 Ar 분위기에서 FeO-TiO₂-MgO-Al₂O₃ 다원계 슬래그와 Ti 함량 60wt% 이상의 Fe-Ti 합금의 평형 반응을 통해 합금 내 Ti 손실을 줄이며 불순물인 N과 C 제거에 대한 슬래그 조성의 영향을 조사하였다. Fe-Ti 합금의 Ti 농도는 Ti 터닝 스크랩을 장입하여 제어하였다. 또한, 합금 제조시 Al을 추가 장입하여 Ti보다 우선 산화를 통해 생성된 Al₂O₃가 슬래그에 함유되는 조건에서 슬래그내 γ_TiO 증가하고 합금 내 Ti 손실 감소를 확인하였다. 한편, Al 추가 장입과 관계없이 Fe-Ti 합금내 불순물인 N는 슬래그의 FeO/TiOx비가 감소할수록 약 0.02wt% 이하로 감소하며, C는 0.1wt% 이하로 감소하는 것을 확인하였다. Fe-Ti 합금내 생성된 평형 산화물은 TiO 상으로 확인되었다. Fe-Ti 합금 내 Ti 손실을 줄이기 위해서는 Ti보다 우선 산화 반응이 일어나는 첨가물이 필요하다고 판단된다.

키워드

페로 티타늄

고온 평형 반응

티타늄 터닝스크랩

재활용

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Information

Publisher :The Korean Institute of Resources Recycling
Publisher(Ko) :한국자원리싸이클링학회
Journal Title :Resources Recycling
Journal Title(Ko) :자원리싸이클링
Volume : 34
No :4
Pages :40-47
Received Date : 2025-05-21
Revised Date : 2025-06-24
Accepted Date : 2025-07-09
DOI :https://doi.org/10.7844/kirr.2025.34.4.40

Resources Recycling ISSN:2765-3439(Print) 2765-3447(Online) 자원리싸이클링

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