Reaction kinetics study of hydrogen reduction of high energy milled CoCrFeNi high-entropy alloy (HEA)
In this study, an equimolar CoCrFeNi high-entropy alloy (HEA) was fabricated via ball milling and hydrogen reduction to assess the feasibility of hydrogen reduction of chromium oxide in chromium based HEAs. High-energy milling of metal oxide powders (Co3O4, Cr2O3, NiO and α-Fe2O3) at 2400 rpm produc...
Saved in:
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2025-03-01
|
| Series: | Journal of Materials Research and Technology |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2238785425004430 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850044346136526848 |
|---|---|
| author | Gertrude Mugwe Mongella Taehyeob Im Minjong Kim Caroline Sunyong Lee |
| author_facet | Gertrude Mugwe Mongella Taehyeob Im Minjong Kim Caroline Sunyong Lee |
| author_sort | Gertrude Mugwe Mongella |
| collection | DOAJ |
| description | In this study, an equimolar CoCrFeNi high-entropy alloy (HEA) was fabricated via ball milling and hydrogen reduction to assess the feasibility of hydrogen reduction of chromium oxide in chromium based HEAs. High-energy milling of metal oxide powders (Co3O4, Cr2O3, NiO and α-Fe2O3) at 2400 rpm produced a homogeneous solid solution, with particle sizes reduced from 60.74 nm at 5 h and 39.84 nm at 30 h milling time. Thermogravimetric analysis (TGA) at varying heating rates was employed, and the Kissinger–Akahira–Sunose (KAS) method was used to compare the reaction kinetics between 5 h and 30 h milled HEA. The 5 h milled HEA reached a conversion fraction of reaction up to 0.71 at 996 °C, while the 30 h milled HEA achieved a conversion of approximately 0.75 at 881 °C. TGA analysis of 30 h milled HEA revealed a 17.3% degree of Cr2O3 reduction without holding time and 52.7 % degree of Cr2O3 reduction after 3 h hold at 1000 °C. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD) confirmed nano-sizing, homogeneity, and phase transformation with increased milling time. The results demonstrate that extended milling enhances microstructural development and hydrogen reduction, potentially making this process a viable alternative to gas atomization for creating CoCrFeNi HEA nanopowder agglomerates for specialized applications. |
| format | Article |
| id | doaj-art-d4f5c2000861480ea4ff27442e1beee9 |
| institution | DOAJ |
| issn | 2238-7854 |
| language | English |
| publishDate | 2025-03-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Materials Research and Technology |
| spelling | doaj-art-d4f5c2000861480ea4ff27442e1beee92025-08-20T02:54:59ZengElsevierJournal of Materials Research and Technology2238-78542025-03-01355591559910.1016/j.jmrt.2025.02.196Reaction kinetics study of hydrogen reduction of high energy milled CoCrFeNi high-entropy alloy (HEA)Gertrude Mugwe Mongella0Taehyeob Im1Minjong Kim2Caroline Sunyong Lee3Department of Materials and Chemical Engineering, Hanyang University, ERICA, Republic of KoreaDepartment of Materials and Chemical Engineering, Hanyang University, ERICA, Republic of KoreaDepartment of Materials and Chemical Engineering, Hanyang University, ERICA, Republic of KoreaCorresponding author.; Department of Materials and Chemical Engineering, Hanyang University, ERICA, Republic of KoreaIn this study, an equimolar CoCrFeNi high-entropy alloy (HEA) was fabricated via ball milling and hydrogen reduction to assess the feasibility of hydrogen reduction of chromium oxide in chromium based HEAs. High-energy milling of metal oxide powders (Co3O4, Cr2O3, NiO and α-Fe2O3) at 2400 rpm produced a homogeneous solid solution, with particle sizes reduced from 60.74 nm at 5 h and 39.84 nm at 30 h milling time. Thermogravimetric analysis (TGA) at varying heating rates was employed, and the Kissinger–Akahira–Sunose (KAS) method was used to compare the reaction kinetics between 5 h and 30 h milled HEA. The 5 h milled HEA reached a conversion fraction of reaction up to 0.71 at 996 °C, while the 30 h milled HEA achieved a conversion of approximately 0.75 at 881 °C. TGA analysis of 30 h milled HEA revealed a 17.3% degree of Cr2O3 reduction without holding time and 52.7 % degree of Cr2O3 reduction after 3 h hold at 1000 °C. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD) confirmed nano-sizing, homogeneity, and phase transformation with increased milling time. The results demonstrate that extended milling enhances microstructural development and hydrogen reduction, potentially making this process a viable alternative to gas atomization for creating CoCrFeNi HEA nanopowder agglomerates for specialized applications.http://www.sciencedirect.com/science/article/pii/S2238785425004430CoCrFeNiHigh-entropy alloyMillingHydrogen reduction |
| spellingShingle | Gertrude Mugwe Mongella Taehyeob Im Minjong Kim Caroline Sunyong Lee Reaction kinetics study of hydrogen reduction of high energy milled CoCrFeNi high-entropy alloy (HEA) Journal of Materials Research and Technology CoCrFeNi High-entropy alloy Milling Hydrogen reduction |
| title | Reaction kinetics study of hydrogen reduction of high energy milled CoCrFeNi high-entropy alloy (HEA) |
| title_full | Reaction kinetics study of hydrogen reduction of high energy milled CoCrFeNi high-entropy alloy (HEA) |
| title_fullStr | Reaction kinetics study of hydrogen reduction of high energy milled CoCrFeNi high-entropy alloy (HEA) |
| title_full_unstemmed | Reaction kinetics study of hydrogen reduction of high energy milled CoCrFeNi high-entropy alloy (HEA) |
| title_short | Reaction kinetics study of hydrogen reduction of high energy milled CoCrFeNi high-entropy alloy (HEA) |
| title_sort | reaction kinetics study of hydrogen reduction of high energy milled cocrfeni high entropy alloy hea |
| topic | CoCrFeNi High-entropy alloy Milling Hydrogen reduction |
| url | http://www.sciencedirect.com/science/article/pii/S2238785425004430 |
| work_keys_str_mv | AT gertrudemugwemongella reactionkineticsstudyofhydrogenreductionofhighenergymilledcocrfenihighentropyalloyhea AT taehyeobim reactionkineticsstudyofhydrogenreductionofhighenergymilledcocrfenihighentropyalloyhea AT minjongkim reactionkineticsstudyofhydrogenreductionofhighenergymilledcocrfenihighentropyalloyhea AT carolinesunyonglee reactionkineticsstudyofhydrogenreductionofhighenergymilledcocrfenihighentropyalloyhea |