J. Mater. Sci. Technol. ›› 2025, Vol. 221: 220-232.DOI: 10.1016/j.jmst.2024.08.067

• Research Article • Previous Articles     Next Articles

Fundamental approach to superior trade-off between strength and ductility of TiB/Ti64 composites via additive manufacturing: From phase diagram to microstructural design

Chen-Wei Liua,1, Jianchao Lia,1, Xiang Gaoa,b,*, Yongkun Muc, Zhouyang Hec, Huan Wanga, Yandong Jiac,*, Bo Yuand, Gang Wangc, Hua-Xin Penga,*   

  1. aInstitute for Composites Science Innovation (InCSI), School of Materials Science and Engineering, Zhejiang University, Hangzhou, 300027, China;
    bNingbo Innovation Center, Zhejiang University, Ningbo, 315100, China;
    cInstitute of Materials, Shanghai University, Shanghai, 200444, China;
    dInstitute of Intelligent Manufacturing Technology, Shenzhen Polytechnic University, Shenzhen, 518055, China
  • Received:2024-07-03 Revised:2024-08-26 Accepted:2024-08-26 Published:2024-10-17 Online:2024-10-17
  • Contact: *E-mail addresses:gaoxiang1986@zju.edu.cn (X. Gao), yandongjia@shu.edu.cn (Y. Jia), hxpengwork@zju.edu.cn (H.-X. Peng)
  • About author:1 These authors contributed equally to this work.

Abstract: Reinforcement distribution tailoring has been proven effective in strengthening and toughening titanium matrix composites (TMCs). In this work, the analysis of the Ti64 (Ti-6Al-4V)-B phase diagram indicated that B content dominates the TiB distribution. With this philosophy, B content regulation was applied to tailor homogeneous and network structures in Ti64-B composites fabricated via laser-directed energy deposition additive manufacturing (AM). The unique plate-like TiB attends inhomogeneous composites (Ti64-0.05B). However, in network composite (Ti64-0.25B), the TiB whisker (TiBw) arranges along prior β-Ti grains with the same orientation. Moreover, the synergistic improvement of strength (988 MPa → 1202 MPa), stiffness (106 GPa → 116 GPa), hardness (325 HV → 362 HV), and uniform elongation (5% → 7.8%) were achieved. This work exhibited a balanced strength/ductility trade-off, which provides a good guide on microstructure tailoring.

Key words: Titanium-matrix composites (TMCs), Additive manufacturing (AM), Reinforcement distribution tailoring, Strength/ductility trade-off, Composition regulation