TY - JOUR
T1 - Microstructure and mechanical properties of Ti 2 AlNb-based alloys synthesized by spark plasma sintering from pre-alloyed and ball-milled powder
AU - Li, Mengchen
AU - Cai, Qi
AU - Liu, Yongchang
AU - Ma, Zongqing
AU - Wang, Zumin
N1 - Publisher Copyright:
© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
PY - 2018/4
Y1 - 2018/4
N2 - Ti 2 AlNb-based alloys are synthesized by spark plasma sintering from pre-alloyed and ball-milled Ti-22Al-25Nb powder, and the structure of the alloys is regulated by aging at 800°C for 0.5, 1, 2, and 3 h. Comparison of phase composition, microstructure, and mechanical properties are made in this study. Aging in the B2 +O phase region refers to the reversible transformation of B2 ↔ O. Complete B2 + O Widmanstätten structure is obtained in the aged alloys synthesized from pre-alloyed powder, and the ones from milled powder contain acicular O and B2 + O Widmanstätten structure. Ball milling eliminates the B2 +O colonies, facilitates the continuous transformation of O → B2, and induces acicular O in the alloys; however, the hardness of these alloys is decreased in contrast with that of the ones synthesized from pre-alloyed powder. Owing to the precipitation strengthening based on a large amount of fine O-phase precipitates, the 3 h aged alloy from pre-alloyed powder exhibits comprehensive mechanical properties with Vickers hardness of 448 ±9 HV, ultimate tensile strength of 730 MPa, and elongation of 0.43%.
AB - Ti 2 AlNb-based alloys are synthesized by spark plasma sintering from pre-alloyed and ball-milled Ti-22Al-25Nb powder, and the structure of the alloys is regulated by aging at 800°C for 0.5, 1, 2, and 3 h. Comparison of phase composition, microstructure, and mechanical properties are made in this study. Aging in the B2 +O phase region refers to the reversible transformation of B2 ↔ O. Complete B2 + O Widmanstätten structure is obtained in the aged alloys synthesized from pre-alloyed powder, and the ones from milled powder contain acicular O and B2 + O Widmanstätten structure. Ball milling eliminates the B2 +O colonies, facilitates the continuous transformation of O → B2, and induces acicular O in the alloys; however, the hardness of these alloys is decreased in contrast with that of the ones synthesized from pre-alloyed powder. Owing to the precipitation strengthening based on a large amount of fine O-phase precipitates, the 3 h aged alloy from pre-alloyed powder exhibits comprehensive mechanical properties with Vickers hardness of 448 ±9 HV, ultimate tensile strength of 730 MPa, and elongation of 0.43%.
KW - Microhardness
KW - Powder metallurgy
KW - Tensile properties
KW - Ti AlNb-based alloys
KW - Widmanstätten structure
UR - http://www.scopus.com/inward/record.url?scp=85037645421&partnerID=8YFLogxK
U2 - 10.1002/adem.201700659
DO - 10.1002/adem.201700659
M3 - Article
AN - SCOPUS:85037645421
SN - 1438-1656
VL - 20
JO - Advanced Engineering Materials
JF - Advanced Engineering Materials
IS - 4
M1 - 1700659
ER -