TY - JOUR
T1 - Microstructure and mechanical properties of an α+β Type Ti-4V-0.6O Alloy
AU - Omiya, Masahito
AU - Ueda, Kyosuke
AU - Narushima, Takayuki
N1 - Funding Information:
The authors would like to thank Dr. K. Kobayashi of To-hoku University for the TEM analyses. This study was partially supported by the Grant in Aid for Science Research from the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan (Nos. 25249094 and 26709049), Iketani Science and Technology Foundation, and The Light Metal Educational Foundation, Inc.
Publisher Copyright:
© 2017 The Japan Institute of Metals and Materials.
PY - 2017
Y1 - 2017
N2 - This paper describes the design of a low-cost α+β type Ti-4V-0.6O alloy and the investigation of its microstructure and mechanical properties, with a focus on heat treatability. The β transus (Tβ) of the alloy was found to be 1195 K, as determined from the relationship between the heat treatment temperature and the volume fraction of the equiaxed α phase (fα). The formation of α′ martensite exhibiting an acicular morphology was observed after heat treatments between 1073 and 1273 K. The O content in the equiaxed α and β phases increased with increasing heat treatment temperature while the V content increased with decreasing heat treatment temperature. The alloy demonstrated a higher tensile strength and lower total elongation when heat-Treated between 1073 and 1173 K as compared to the as-forged material, because of the formation of α′ martensite. The reduced total elongation was caused by the increase in the hardness difference between the equiaxed α and β (α′ martensite) grains. The tensile strength and total elongation of the Ti-4V-0.6O alloy were comparable to those of the Ti-6Al-4V alloy, which marks the material as a low-cost α+β type Ti alloy candidate.
AB - This paper describes the design of a low-cost α+β type Ti-4V-0.6O alloy and the investigation of its microstructure and mechanical properties, with a focus on heat treatability. The β transus (Tβ) of the alloy was found to be 1195 K, as determined from the relationship between the heat treatment temperature and the volume fraction of the equiaxed α phase (fα). The formation of α′ martensite exhibiting an acicular morphology was observed after heat treatments between 1073 and 1273 K. The O content in the equiaxed α and β phases increased with increasing heat treatment temperature while the V content increased with decreasing heat treatment temperature. The alloy demonstrated a higher tensile strength and lower total elongation when heat-Treated between 1073 and 1173 K as compared to the as-forged material, because of the formation of α′ martensite. The reduced total elongation was caused by the increase in the hardness difference between the equiaxed α and β (α′ martensite) grains. The tensile strength and total elongation of the Ti-4V-0.6O alloy were comparable to those of the Ti-6Al-4V alloy, which marks the material as a low-cost α+β type Ti alloy candidate.
KW - Distribution coefficient
KW - Heat treatment
KW - Mechanical properties
KW - Oxygen
KW - α+β type titanium alloy
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U2 - 10.2320/matertrans.L-M2017825
DO - 10.2320/matertrans.L-M2017825
M3 - Article
AN - SCOPUS:85028349424
VL - 58
SP - 1250
EP - 1256
JO - Materials Transactions
JF - Materials Transactions
SN - 1345-9678
IS - 9
ER -