中國有色金屬學報(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 33 No. 11 November 2023 |
（1. Key Laboratory for Materials Modification by Laser, Ion, and Electron Beams of Ministry of Education, School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, China;
2. State Key Laboratory of Light Alloy Casting Technology for High-end Equipment, Shenyang Research Institute of Foundry Co., Ltd., Shenyang 110022, China;
3. School of Materials Science and Engineering, Dalian Jiaotong University, Dalian 116028, China）
Abstract:A near-α Ti-7Al-2V alloy was designed using cluster formula approach and prepared by laser additive manufacturing, whose specific strength is better than that of Ti-6Al-4V alloy. Its composition formula α-{[Al-Ti12](AlTi2)}15+β-{[Al-Ti14](V3)}2 features an enhanced α-Ti by increasing α unit proportion of 15/17 (with respect to 12/17 of Ti-6Al-4V alloy) and stabilized β-Ti via V alloying. This alloy possesses a good laser additive manufacturing processibility. At the as-deposited state, the microstructures are composed of fine basket-weave regions, coarse basket-weave regions and ultrafine α Widmanst？tten lath regions. The surface roughness of coarse basket-weave regions is much smaller than that of fine basket-weave regions and ultrafine α Widmanst？tten lath regions. The α-phase distribution in fine basket-weave regions is more uniform than that in the coarse basket-weave regions. Its ultimate tensile strength of 971-1005 MPa, yield strength of 891-921 MPa and elongation of 4.5%-6.6% are close to those of Ti-6Al-4V alloy, and particularly, its specific strength of 224-232 kN·m/kg is better than that of Ti-6Al-4V alloy.
Key words: Ti alloy; composition design; cluster-plus-glue-atom model; laser additive manufacturing; mechanical properties
