TY - JOUR
T1 - Discontinuous yielding and microstructural evolution of Ti-40 at.% Al alloy compressed in single α-hcp phase region
AU - Wei, Dai Xiu
AU - Koizumi, Yuichiro
AU - Chiba, Akihiko
N1 - Funding Information:
This work was supported by a Grant-In-Aid for Scientific Research in a Priority Area on “Creation of Life Innovation Materials for Interdisciplinary and International Researcher Development” from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan .
Publisher Copyright:
© 2016 Elsevier B.V.
PY - 2017/2/5
Y1 - 2017/2/5
N2 - We examined the hot deformation behaviors of Ti-40 at.% Al alloy via hot compression tests at temperatures in the range of 1423–1523 K (single α-hcp phase) at strain rates in the range of 1–0.001 s−1. Specifically, we investigated the discontinuous yielding phenomenon and the strain rate dependence of the microstructural evolution of the alloy. Sharp drops in flow stresses occurred during hot compression at strain rates of 1 s−1 and 0.1 s−1, which were attributed mainly to both the multiplication of dislocations and the formation of deformation twins. The twins were determined as being of the compound type with the following twin elements: K1: {112¯1}, K2: {112¯2¯}, η1: <112¯6¯>, η2: <112¯3>, s = 0.232. The grains of the α2-Ti3Al single phase were more significantly refined and homogenized by hot compression at a high strain rate of 1 s−1 than at a low strain rate of 0.001 s−1, with the assistance of the deformation twins at the high strain rate.
AB - We examined the hot deformation behaviors of Ti-40 at.% Al alloy via hot compression tests at temperatures in the range of 1423–1523 K (single α-hcp phase) at strain rates in the range of 1–0.001 s−1. Specifically, we investigated the discontinuous yielding phenomenon and the strain rate dependence of the microstructural evolution of the alloy. Sharp drops in flow stresses occurred during hot compression at strain rates of 1 s−1 and 0.1 s−1, which were attributed mainly to both the multiplication of dislocations and the formation of deformation twins. The twins were determined as being of the compound type with the following twin elements: K1: {112¯1}, K2: {112¯2¯}, η1: <112¯6¯>, η2: <112¯3>, s = 0.232. The grains of the α2-Ti3Al single phase were more significantly refined and homogenized by hot compression at a high strain rate of 1 s−1 than at a low strain rate of 0.001 s−1, with the assistance of the deformation twins at the high strain rate.
KW - Discontinuous yielding
KW - Hot deformation
KW - Titanium aluminides
KW - Twinning
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U2 - 10.1016/j.jallcom.2016.10.080
DO - 10.1016/j.jallcom.2016.10.080
M3 - Article
AN - SCOPUS:84992559997
SN - 0925-8388
VL - 693
SP - 1261
EP - 1276
JO - Journal of Alloys and Compounds
JF - Journal of Alloys and Compounds
ER -