Improvement on high-temperature tensile strength and ductility of selective electron beam melting TiAl alloys via small-strain forging

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review

3 Scopus Citations
View graph of relations

Author(s)

  • Hui Tao
  • Huizhong Li
  • Li Wang
  • Yixuan Che
  • Weiwei He
  • Huixia Li
  • Xiaopeng Liang

Detail(s)

Original languageEnglish
Article number145009
Journal / PublicationMaterials Science and Engineering A
Volume873
Online published6 Apr 2023
Publication statusPublished - 17 May 2023

Abstract

In the present work, a Ti–48Al–2Cr–2Nb alloy prepared by selective electron beam melting (SEBM) and post-treated by forging at a small strain was investigated. The results show that the microstructure of the as-built TiAl alloys exhibited an alternating layer of coarse single γ grains and fine γ+α2 grains configuration along the building direction. After forging at a small strain, the fraction of the coarsely grained region decreases, and substantial fine sub-grains form in the fine-grained region. Additionally, fractions of the α2 phase and α2/γ lamellar colonies increase. These factors lead to an increase in the tensile strength of alloys. Meanwhile, the low-angle grain boundaries (LAGBs) in fine sub-grains and the substantial mobile dislocations in coarse γ grains are favorable for improving the ductility of alloys. The formation of deformation twins in the γ grains facilitates the simultaneous improvement of strength and ductility. In addition, the anisotropy of tensile properties is reduced after small-strain forging, which can be attributed to the reduction in fraction of the coarse γ grains, and the increase in the fractions of the α2 phase and α2/γ lamellar structure. Therefore, small-strain forging was verified as an effective post-treatment method for the improvement of tensile strength and ductility of SEBM prepared TiAl alloys at high temperatures. © 2023 Elsevier B.V.

Research Area(s)

  • High-temperature tensile properties, Selective electron beam melting, Small-strain forging, Titanium aluminides

Citation Format(s)

Improvement on high-temperature tensile strength and ductility of selective electron beam melting TiAl alloys via small-strain forging. / Tao, Hui; Li, Huizhong; Wang, Li et al.
In: Materials Science and Engineering A, Vol. 873, 145009, 17.05.2023.

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review