Evolution of sigma phase precipitates in Cu-containing 25Cr–20Ni austenitic stainless steels
This study investigated, for the first time, the influence of Cu addition on sigma phase precipitation during aging at 700 °C in recrystallized 25Cr–20Ni austenitic stainless steels containing up to 2.9 wt% Cu. The sigma phase degrades the mechanical properties of steels. Microstructural analyses sh...
Saved in:
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2025-05-01
|
| Series: | Journal of Materials Research and Technology |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S223878542501405X |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850182919512915968 |
|---|---|
| author | Gunjick Lee Heechan Jung Han Jun Yu Jung Hun Han Seok Su Sohn Jae-Hyeok Shim |
| author_facet | Gunjick Lee Heechan Jung Han Jun Yu Jung Hun Han Seok Su Sohn Jae-Hyeok Shim |
| author_sort | Gunjick Lee |
| collection | DOAJ |
| description | This study investigated, for the first time, the influence of Cu addition on sigma phase precipitation during aging at 700 °C in recrystallized 25Cr–20Ni austenitic stainless steels containing up to 2.9 wt% Cu. The sigma phase degrades the mechanical properties of steels. Microstructural analyses showed that Cu addition significantly reduced sigma precipitation during aging for up to 1,000 h. However, in the early stages of aging, the amount of the sigma phase was slightly higher in the Cu-containing samples than in the sample without Cu. The amount of the sigma phase in the samples aged for 1,000 h was reduced 15.3, 8.8 and 7.6 % in the samples with 0, 1.4, and 2.9 wt% Cu, respectively. Interestingly, Cu-enriched layers were observed around sigma phase precipitates, which were presumed to consist of Cu atoms expelled from sigma phase precipitates with very limited Cu solubility. These layers seemed to play a crucial role in retarding the growth of the sigma phase in the samples with Cu. Tensile test results for the samples aged for 1,000 h indicated that the elongation of all the samples was significantly reduced compared to that of the recrystallized samples owing to the sigma phase precipitation. Nevertheless, the elongation losses of the samples with 1.4 and 2.9 wt% Cu were much smaller than those of the sample without Cu. |
| format | Article |
| id | doaj-art-24ddae2db3074cbbb32d4ccfbb32883a |
| institution | OA Journals |
| issn | 2238-7854 |
| language | English |
| publishDate | 2025-05-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Materials Research and Technology |
| spelling | doaj-art-24ddae2db3074cbbb32d4ccfbb32883a2025-08-20T02:17:29ZengElsevierJournal of Materials Research and Technology2238-78542025-05-0136102341024210.1016/j.jmrt.2025.05.249Evolution of sigma phase precipitates in Cu-containing 25Cr–20Ni austenitic stainless steelsGunjick Lee0Heechan Jung1Han Jun Yu2Jung Hun Han3Seok Su Sohn4Jae-Hyeok Shim5Center for Hydrogen Energy Materials, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea; Department of Materials Science and Engineering, Korea University, Seoul, 02841, Republic of KoreaDepartment of Materials Science and Engineering, Korea University, Seoul, 02841, Republic of KoreaCenter for Hydrogen Energy Materials, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of KoreaDepartment of Materials Science and Engineering, Korea University, Seoul, 02841, Republic of KoreaDepartment of Materials Science and Engineering, Korea University, Seoul, 02841, Republic of Korea; Corresponding author.Center for Hydrogen Energy Materials, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea; KIST-SKKU Carbon-Neutral Research Center, Sungkyunkwan University (SKKU), Suwon, Gyeonggi, 02841, Republic of Korea; Corresponding author. Center for Hydrogen Energy Materials, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea.This study investigated, for the first time, the influence of Cu addition on sigma phase precipitation during aging at 700 °C in recrystallized 25Cr–20Ni austenitic stainless steels containing up to 2.9 wt% Cu. The sigma phase degrades the mechanical properties of steels. Microstructural analyses showed that Cu addition significantly reduced sigma precipitation during aging for up to 1,000 h. However, in the early stages of aging, the amount of the sigma phase was slightly higher in the Cu-containing samples than in the sample without Cu. The amount of the sigma phase in the samples aged for 1,000 h was reduced 15.3, 8.8 and 7.6 % in the samples with 0, 1.4, and 2.9 wt% Cu, respectively. Interestingly, Cu-enriched layers were observed around sigma phase precipitates, which were presumed to consist of Cu atoms expelled from sigma phase precipitates with very limited Cu solubility. These layers seemed to play a crucial role in retarding the growth of the sigma phase in the samples with Cu. Tensile test results for the samples aged for 1,000 h indicated that the elongation of all the samples was significantly reduced compared to that of the recrystallized samples owing to the sigma phase precipitation. Nevertheless, the elongation losses of the samples with 1.4 and 2.9 wt% Cu were much smaller than those of the sample without Cu.http://www.sciencedirect.com/science/article/pii/S223878542501405XSigma phasePrecipitateAustenitic stainless steelAgingElectron backscatter diffractionCu-enriched layer |
| spellingShingle | Gunjick Lee Heechan Jung Han Jun Yu Jung Hun Han Seok Su Sohn Jae-Hyeok Shim Evolution of sigma phase precipitates in Cu-containing 25Cr–20Ni austenitic stainless steels Journal of Materials Research and Technology Sigma phase Precipitate Austenitic stainless steel Aging Electron backscatter diffraction Cu-enriched layer |
| title | Evolution of sigma phase precipitates in Cu-containing 25Cr–20Ni austenitic stainless steels |
| title_full | Evolution of sigma phase precipitates in Cu-containing 25Cr–20Ni austenitic stainless steels |
| title_fullStr | Evolution of sigma phase precipitates in Cu-containing 25Cr–20Ni austenitic stainless steels |
| title_full_unstemmed | Evolution of sigma phase precipitates in Cu-containing 25Cr–20Ni austenitic stainless steels |
| title_short | Evolution of sigma phase precipitates in Cu-containing 25Cr–20Ni austenitic stainless steels |
| title_sort | evolution of sigma phase precipitates in cu containing 25cr 20ni austenitic stainless steels |
| topic | Sigma phase Precipitate Austenitic stainless steel Aging Electron backscatter diffraction Cu-enriched layer |
| url | http://www.sciencedirect.com/science/article/pii/S223878542501405X |
| work_keys_str_mv | AT gunjicklee evolutionofsigmaphaseprecipitatesincucontaining25cr20niausteniticstainlesssteels AT heechanjung evolutionofsigmaphaseprecipitatesincucontaining25cr20niausteniticstainlesssteels AT hanjunyu evolutionofsigmaphaseprecipitatesincucontaining25cr20niausteniticstainlesssteels AT junghunhan evolutionofsigmaphaseprecipitatesincucontaining25cr20niausteniticstainlesssteels AT seoksusohn evolutionofsigmaphaseprecipitatesincucontaining25cr20niausteniticstainlesssteels AT jaehyeokshim evolutionofsigmaphaseprecipitatesincucontaining25cr20niausteniticstainlesssteels |