Bibliographic Details
| Title: |
Synergistic effects of Ti–N–B additions on microstructure refinement and toughness enhancement in high-heat-input welded CGHAZ |
| Authors: |
Junjie Hao, Chao Wang, Hua Duan, Zhu Yan, Guo Yuan, Guo-dong Wang |
| Source: |
Journal of Materials Research and Technology, Vol 38, Iss, Pp 692-701 (2025) |
| Publisher Information: |
Elsevier BV, 2025. |
| Publication Year: |
2025 |
| Subject Terms: |
BN, Coarse grained heat-affected zone (CGHAZ), Mining engineering. Metallurgy, High-heat-input welding, TN1-997, TiN particles, In situ |
| Description: |
High-heat-input welding enhances construction efficiency but deteriorates toughness in the coarse-grained heat-affected zone due to austenite grain coarsening and brittle microstructures. This study investigates Ti–N–B synergy to mitigate these issues under 400 kJ/cm electrogas arc welding. Three steel variants—base Ti–N steel, high-N steel, and high-N-B steel—were designed, and their microstructural evolution, impact toughness, and phase transformation behavior were analyzed through Charpy testing, optical/scanning electron microscopy, and in situ laser scanning confocal microscopy. Results show that the base steel exhibits an impact toughness of 126 ± 37 J. The high-N steel displayed significantly refined prior austenite grains compared with the base steel, yet higher levels of free nitrogen resulted in a pronounced reduction in toughness to 46 ± 15 J. Conversely, boron addition in the high-N-B steel effectively precipitated N as BN, reducing free N content and achieving superior impact toughness of 154 ± 16 J. BN-TiN-MnS composite inclusions promoted intragranular ferrite nucleation, suppressing brittle grain boundary phases. Thermodynamic analysis confirmed the sequential precipitation of TiN and BN during thermal cycling, which synergistically refined grain structures and mitigated free N embrittlement, thereby significantly enhancing toughness. |
| Document Type: |
Article |
| Language: |
English |
| ISSN: |
2238-7854 |
| DOI: |
10.1016/j.jmrt.2025.07.209 |
| Access URL: |
https://doaj.org/article/7347663781f5406c912e69d9fe1ec002 |
| Rights: |
CC BY NC ND |
| Accession Number: |
edsair.doi.dedup.....78de3bb9cd21d9045210e2c6def3bd53 |
| Database: |
OpenAIRE |