Effect of Ti and TiNb Microalloying on Microstructures and Mechanical Properties of 2200 MPa Low-Alloy Ultra-High-Strength Steels
The 2200 MPa low-alloy ultra-high-strength steels microalloyed with Ti (Ti-steel) and Ti and Nb (TiNb-steel) were quenched at 860 °C and tempered at 180 °C, and the mechanical properties, microstructure, and precipitated phase were studied by SEM, TEM, and physicochemical phase analysis. The results...
Saved in:
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2025-02-01
|
| Series: | Metals |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2075-4701/15/3/235 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850280064092995584 |
|---|---|
| author | Wenchao Yu Ruizhe Jin Lei Han Dirong Xie Ting Sun Maoqiu Wang Jie Shi |
| author_facet | Wenchao Yu Ruizhe Jin Lei Han Dirong Xie Ting Sun Maoqiu Wang Jie Shi |
| author_sort | Wenchao Yu |
| collection | DOAJ |
| description | The 2200 MPa low-alloy ultra-high-strength steels microalloyed with Ti (Ti-steel) and Ti and Nb (TiNb-steel) were quenched at 860 °C and tempered at 180 °C, and the mechanical properties, microstructure, and precipitated phase were studied by SEM, TEM, and physicochemical phase analysis. The results of mechanical properties showed that the TiNb-steel had higher strength than the Ti-steel, with a yield strength of 1746 MPa and 1802 MPa and a tensile strength of 2198 MPa and 2232 MPa, respectively. The TiNb-steel had a finer structure than the Ti-steel, with the effective grain sizes being 0.86 μm and 1 μm, respectively. The TiNb-steel had more MC-type carbides than the Ti-steel, and the MC-type carbide contents were 0.24 wt.% and 0.19 wt.%, respectively. The reason for the higher yield strength of the TiNb-steel is that it has higher strengthening effects due to finer grains, a higher density of dislocation, and more precipitation. The reason for the higher tensile strength of the TiNb-steel is that it has a higher coefficient of variable hardening K and a higher strain hardening index n. |
| format | Article |
| id | doaj-art-5e2cd5cc9a93491d9e5c36af5cc62e0a |
| institution | OA Journals |
| issn | 2075-4701 |
| language | English |
| publishDate | 2025-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Metals |
| spelling | doaj-art-5e2cd5cc9a93491d9e5c36af5cc62e0a2025-08-20T01:48:53ZengMDPI AGMetals2075-47012025-02-0115323510.3390/met15030235Effect of Ti and TiNb Microalloying on Microstructures and Mechanical Properties of 2200 MPa Low-Alloy Ultra-High-Strength SteelsWenchao Yu0Ruizhe Jin1Lei Han2Dirong Xie3Ting Sun4Maoqiu Wang5Jie Shi6Central Iron & Steel Research Institute Company Limited, Beijing 100081, ChinaCentral Iron & Steel Research Institute Company Limited, Beijing 100081, ChinaInner Mongolia First Machinery Group Co., Ltd., Baotou 014030, ChinaHunan Valin Lianyuan Iron and Steel Co., Ltd., Loudi 417009, ChinaCentral Iron & Steel Research Institute Company Limited, Beijing 100081, ChinaCentral Iron & Steel Research Institute Company Limited, Beijing 100081, ChinaCentral Iron & Steel Research Institute Company Limited, Beijing 100081, ChinaThe 2200 MPa low-alloy ultra-high-strength steels microalloyed with Ti (Ti-steel) and Ti and Nb (TiNb-steel) were quenched at 860 °C and tempered at 180 °C, and the mechanical properties, microstructure, and precipitated phase were studied by SEM, TEM, and physicochemical phase analysis. The results of mechanical properties showed that the TiNb-steel had higher strength than the Ti-steel, with a yield strength of 1746 MPa and 1802 MPa and a tensile strength of 2198 MPa and 2232 MPa, respectively. The TiNb-steel had a finer structure than the Ti-steel, with the effective grain sizes being 0.86 μm and 1 μm, respectively. The TiNb-steel had more MC-type carbides than the Ti-steel, and the MC-type carbide contents were 0.24 wt.% and 0.19 wt.%, respectively. The reason for the higher yield strength of the TiNb-steel is that it has higher strengthening effects due to finer grains, a higher density of dislocation, and more precipitation. The reason for the higher tensile strength of the TiNb-steel is that it has a higher coefficient of variable hardening K and a higher strain hardening index n.https://www.mdpi.com/2075-4701/15/3/235low-alloy ultra-high-strength steelsmicroalloyingmicrostructuremechanical propertiesstrengthening mechanism |
| spellingShingle | Wenchao Yu Ruizhe Jin Lei Han Dirong Xie Ting Sun Maoqiu Wang Jie Shi Effect of Ti and TiNb Microalloying on Microstructures and Mechanical Properties of 2200 MPa Low-Alloy Ultra-High-Strength Steels Metals low-alloy ultra-high-strength steels microalloying microstructure mechanical properties strengthening mechanism |
| title | Effect of Ti and TiNb Microalloying on Microstructures and Mechanical Properties of 2200 MPa Low-Alloy Ultra-High-Strength Steels |
| title_full | Effect of Ti and TiNb Microalloying on Microstructures and Mechanical Properties of 2200 MPa Low-Alloy Ultra-High-Strength Steels |
| title_fullStr | Effect of Ti and TiNb Microalloying on Microstructures and Mechanical Properties of 2200 MPa Low-Alloy Ultra-High-Strength Steels |
| title_full_unstemmed | Effect of Ti and TiNb Microalloying on Microstructures and Mechanical Properties of 2200 MPa Low-Alloy Ultra-High-Strength Steels |
| title_short | Effect of Ti and TiNb Microalloying on Microstructures and Mechanical Properties of 2200 MPa Low-Alloy Ultra-High-Strength Steels |
| title_sort | effect of ti and tinb microalloying on microstructures and mechanical properties of 2200 mpa low alloy ultra high strength steels |
| topic | low-alloy ultra-high-strength steels microalloying microstructure mechanical properties strengthening mechanism |
| url | https://www.mdpi.com/2075-4701/15/3/235 |
| work_keys_str_mv | AT wenchaoyu effectoftiandtinbmicroalloyingonmicrostructuresandmechanicalpropertiesof2200mpalowalloyultrahighstrengthsteels AT ruizhejin effectoftiandtinbmicroalloyingonmicrostructuresandmechanicalpropertiesof2200mpalowalloyultrahighstrengthsteels AT leihan effectoftiandtinbmicroalloyingonmicrostructuresandmechanicalpropertiesof2200mpalowalloyultrahighstrengthsteels AT dirongxie effectoftiandtinbmicroalloyingonmicrostructuresandmechanicalpropertiesof2200mpalowalloyultrahighstrengthsteels AT tingsun effectoftiandtinbmicroalloyingonmicrostructuresandmechanicalpropertiesof2200mpalowalloyultrahighstrengthsteels AT maoqiuwang effectoftiandtinbmicroalloyingonmicrostructuresandmechanicalpropertiesof2200mpalowalloyultrahighstrengthsteels AT jieshi effectoftiandtinbmicroalloyingonmicrostructuresandmechanicalpropertiesof2200mpalowalloyultrahighstrengthsteels |