TY - JOUR
T1 - Individual and synergistic effects of Ta and Mn on optimizing the microstructures and mechanical properties of TiB reinforced high Nb–TiAl composites
AU - Chen, Siyu
AU - Tan, Yingmei
AU - Wang, Xuan
AU - Cao, Feng
AU - Wang, Liang
AU - Su, Yanqing
AU - Guo, Jingjie
N1 - Publisher Copyright:
© 2023 The Authors
PY - 2023/3/1
Y1 - 2023/3/1
N2 - In order to further optimize the microstructure and mechanical properties of TiB/TiAl composites, the individual and synergistic effects of Ta and Mn were investigated in this study. Ti43Al6Nb1.6B-xTa-yMn (x + y = 1, at%) composites, termed as TNB, TNB-1Ta, TNB-1Mn and TNB-0.5Ta0.5Mn, were fabricated by vacuum arc melting. X-ray diffraction results showed that the diffraction peak of B2 phase appeared in TNB-1Ta and TNB-1Mn composites, while it was not obvious in TNB-0.5Ta0.5Mn counterpart, which indicated that higher content of B2 phase formed with individual 1% Ta or 1% Mn addition. According to the solidified microstructures, Ta and/or Mn addition changed the α2/γ lamellar colonies from elongated to equiaxed morphology, which was due to the constitutional undercooling by Ta and/or Mn addition. Compressive results showed that individual and synergistic addition of Ta and Mn all increased the compressive strength and strain at room temperature, while the highest compressive properties were obtained in TNB-0.5Ta0.5Mn, which were 2142 MPa and 25.7%, respectively. Compared with individual addition of Ta or Mn, the synergistic addition of 0.5% Ta and 0.5% Mn not only induced less brittle B2 phase, but also had a stronger solid solution strengthening effect, because Ta atoms existed in TiB phase and Mn atoms existed in α2/γ lamellae. Therefore, the enhanced properties of TNB-0.5Ta0.5Mn resulted from the refinement of α2/γ lamellar colonies, solid solution strengthening of Ta and Mn, and lower content of brittle B2 phase.
AB - In order to further optimize the microstructure and mechanical properties of TiB/TiAl composites, the individual and synergistic effects of Ta and Mn were investigated in this study. Ti43Al6Nb1.6B-xTa-yMn (x + y = 1, at%) composites, termed as TNB, TNB-1Ta, TNB-1Mn and TNB-0.5Ta0.5Mn, were fabricated by vacuum arc melting. X-ray diffraction results showed that the diffraction peak of B2 phase appeared in TNB-1Ta and TNB-1Mn composites, while it was not obvious in TNB-0.5Ta0.5Mn counterpart, which indicated that higher content of B2 phase formed with individual 1% Ta or 1% Mn addition. According to the solidified microstructures, Ta and/or Mn addition changed the α2/γ lamellar colonies from elongated to equiaxed morphology, which was due to the constitutional undercooling by Ta and/or Mn addition. Compressive results showed that individual and synergistic addition of Ta and Mn all increased the compressive strength and strain at room temperature, while the highest compressive properties were obtained in TNB-0.5Ta0.5Mn, which were 2142 MPa and 25.7%, respectively. Compared with individual addition of Ta or Mn, the synergistic addition of 0.5% Ta and 0.5% Mn not only induced less brittle B2 phase, but also had a stronger solid solution strengthening effect, because Ta atoms existed in TiB phase and Mn atoms existed in α2/γ lamellae. Therefore, the enhanced properties of TNB-0.5Ta0.5Mn resulted from the refinement of α2/γ lamellar colonies, solid solution strengthening of Ta and Mn, and lower content of brittle B2 phase.
KW - B2 phase
KW - Element distribution
KW - Mechanical properties
KW - Ta and Mn
KW - TiAl composites
UR - http://www.scopus.com/inward/record.url?scp=85148541788&partnerID=8YFLogxK
U2 - 10.1016/j.jmrt.2023.01.004
DO - 10.1016/j.jmrt.2023.01.004
M3 - Article
AN - SCOPUS:85148541788
SN - 2238-7854
VL - 23
SP - 209
EP - 220
JO - Journal of Materials Research and Technology
JF - Journal of Materials Research and Technology
ER -