J. Mater. Sci. Technol. ›› 2024, Vol. 191: 146-156.DOI: 10.1016/j.jmst.2024.01.011

• Research Article • Previous Articles     Next Articles

Simultaneously enhancing strength and ductility of LPBF Ti alloy via trace Y2 O3 nanoparticle addition

Yinghang Liua, Zhe Songa, Yi Guoa, Gaoming Zhua,b, Yunhao Fana, Huamiao Wangc, Wentao Yand, Xiaoqin Zenga,e, Leyun Wanga,e,f,*   

  1. aNational Engineering Research Center of Light Alloy Net Forming, Shanghai Jiao Tong University, Shanghai 200240, China;
    bDeutsches Elektronen-Synchrotron (DESY), Hamburg 22607, Germany;
    cState Key Laboratory of Mechanical Systems and Vibration, Shanghai Jiao Tong University, Shanghai 200240, China;
    dCollege of Design and Engineering, National University of Singapore, 117575, Singapore;
    eState Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, China;
    fZhangjiang Institute for Advanced Study, Shanghai Jiao Tong University, Shanghai 201203, China
  • Received:2023-09-24 Revised:2023-12-11 Accepted:2024-01-04 Online:2024-08-20
  • Contact: *State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, China. E-mail address: leyunwang@sjtu.edu.cn (L. Wang).

Abstract: Laser powder bed fusion (LPBF) is a popular additive manufacturing (AM) technique to fabricate metal components. LPBF Ti alloys often exhibit high strength but poor ductility. In this study, we report that trace Y2 O3 nanoparticles added to a pre-alloyed Ti-4Al-4V (Ti44) powder provides an excellent feedstock for LPBF. As-built Ti44-Y2 O3 materials exhibited a strength-ductility combination that is slightly better than heat-treated LPBF Ti64. Some Y2 O3 particles may have melted or decomposed during LPBF. From electron microscopy, the addition of Y2 O3 refined α’ martensite laths and weakened variant preference during β→ α’ transformation. Based on in situ synchrotron X-ray diffraction and elastic-viscoplastic self-consistent (EVPSC) modeling, ‹c+a› slip was more active in as-built Ti44-Y2 O3 than in as-built Ti64 or Ti44. This work demonstrates that LPBF can be an excellent method to fabricate metal-nanoparticle composite materials.

Key words: Titanium alloys, Additive manufacturing, Nanoparticles, Ductility, Synchrotron diffraction