Evolution of equiaxed alpha phase during heat treatment in a near alpha titanium alloy

Published on Nov 25, 2017in Journal of Alloys and Compounds4.65
· DOI :10.1016/J.JALLCOM.2017.07.195
Xiongxiong Gao7
Estimated H-index: 7
(NPU: Northwestern Polytechnical University),
Weidong Zeng32
Estimated H-index: 32
(NPU: Northwestern Polytechnical University)
+ 3 AuthorsQingjiang Wang13
Estimated H-index: 13
(CAS: Chinese Academy of Sciences)
Abstract The evolution of equiaxed primary α phase (α p ) during post-deformation heat treatment of near-α titanium alloy Ti-5.6Al-3.8Sn-3.2Zr-1.0Ta-0.5Mo-0.4Nb-0.35Si was studied. This alloy was isothermally compressed at 1019 °C and subsequently heat treatment at 1024 °C for times ranging from 0.5 to 24 h. The recrystallization behavior and boundary splitting within equiaxed α p were analyzed by crystallographic orientation and microstructure observations. The results showed that the formation of internal (sub)boundaries within the α p was by the strong recovery. In most cases, it is difficult to obtain a refinement of big equiaxed α p by boundary splitting and α p grains were still contiguous with “peanut” shape at relatively short heat treatment time (≤24 h, 1024 °C). The groove in the “peanut” structure was indicative of boundary of α/α. Only in a few cases, when an isolated β grain can form within the interior α p along the (sub)boundary, refinement of α p grain may be achieved due to the obvious reduction of boundary splitting distance. These observations were rationalized on the basis of the classical Mullins grooving analysis.
📖 Papers frequently viewed together
1,174 Citations
10 Citations
#1Xiongxiong Gao (NPU: Northwestern Polytechnical University)H-Index: 7
#2Weidong Zeng (NPU: Northwestern Polytechnical University)H-Index: 32
Last. Qingjiang Wang (CAS: Chinese Academy of Sciences)H-Index: 13
view all 4 authors...
Abstract The epitaxial growth behaviors of equiaxed primary α phase (α p ) at different cooling rates (150–0.15 °C/s) in a near α titanium alloy Ti60 were studied by optical micrograph, back scattered electron (BSE) images, high-resolution electron backscatter diffraction technique (EBSD) and electron probe microanalysis (EPMA). Microstructural observations indicated that the size of α p significantly increased with decreasing cooling rate. The rim-α phase observed by BSE image, which formed at ...
38 CitationsSource
#1S. L. Semiatin (AFRL: Air Force Research Laboratory)H-Index: 78
#2F. Sun (Alcoa)H-Index: 1
Last. D. G. SandersH-Index: 1
view all 6 authors...
Coarsening behavior and superplastic-flow response of Ti-6Al-2Sn-4Zr-2Mo-0.1Si with an ultrafine, equiaxed-alpha microstructure were interpreted in the context of classical models. Static coarsening was shown to follow modified Lifshitz–Slyosov–Wagner (LSW) kinetics. The rate of dynamic coarsening was six times more rapid than the corresponding static rate due to enhanced diffusion of solutes in the beta matrix. Last, a generalized constitutive equation was used to interpret the dependence of fl...
5 CitationsSource
#1Wang Qing-jian (CAS: Chinese Academy of Sciences)H-Index: 1
The history of solid solution strengthened high temperature titanium alloys was briefly reviewed and those alloys developed in the UK,USA and Russia were compared. Three kinds of alloys,Ti55,Ti60 and Ti65,covering the temperature range of 550- 650℃,and related welding technology were introduced. Suggestions for perfecting the systematics of high temperature titanium alloys in China are made based on an overview of the status quo. Six key issues that should be tackled in the near future are ident...
26 Citations
#2Jong Woo Won (POSTECH: Pohang University of Science and Technology)H-Index: 12
Last. Chong Soo Lee (POSTECH: Pohang University of Science and Technology)H-Index: 59
view all 5 authors...
The effect of imposed strain e, annealing temperature T A, and annealing time τ on the static spheroidization behavior of Ti-6Al-2Sn-4Zr-2Mo-0.1Si having an initial lamellar microstructure was investigated. For this purpose, the samples were compressed isothermally at 1173 K (900 °C) to e = 1.0 and subsequently annealed at 1228 K (955 °C) ≤ T A ≤ 1253 K (980 °C) for 10 minutes ≤ τ ≤ 24 hours. For each test condition, metallography was performed to evaluate the change in aspect ratio (AR) and thu...
53 CitationsSource
#1Steven Dillien (Katholieke Universiteit Leuven)H-Index: 2
#2Marc Seefeldt (Katholieke Universiteit Leuven)H-Index: 19
Last. Paul Van Houtte (Katholieke Universiteit Leuven)H-Index: 26
view all 5 authors...
Abstract EBSD measurements were performed on as-received and on cold deformed DP600 plate material in order to characterize the substructure development with mechanical straining. Even in the undeformed material, a slight lattice curvature in the ferrite was observed at the phase boundaries with martensitic grains, while such a curvature was not observed at ferrite–ferrite grain boundaries. Upon mechanical straining, a strong curvature develops predominantly around martensitic grains. At high st...
33 CitationsSource
#1S. L. Semiatin (FFO: Wright-Patterson Air Force Base)H-Index: 78
#2T. M. Lehner (UD: University of Dayton)H-Index: 1
Last. D. U. Furrer (Rolls-Royce Motor Cars)H-Index: 1
view all 5 authors...
The effect of alpha/beta solution temperature and cooling rate on the evolution of microstructure during the heat treatment of Ti-6Al-2Sn-4Zr-2Mo-0.1Si (Ti6242Si) with a partially spheroidized starting microstructure of equiaxed + remnant lamellar alpha was established. Experiments comprising induction heating to a peak temperature of 971 °C or 982 °C followed by cooling at a rate of 11 °C/min or 42 °C/min revealed that the volume fraction of the equiaxed alpha grew much more rapidly than the la...
82 CitationsSource
#1Z. GuoH-Index: 19
#2A.P. MiodownikH-Index: 10
Last. J.P. SchilleH-Index: 5
view all 4 authors...
Abstract The stacking-fault energy (SFE) has been incorporated in the calculation of the steady-state creep rate of commercially-pure titanium and Ti–(1–10) mol.% Al alloys. Their creep behaviour was found to follow power-law creep when the dependence of SFE on the aluminium content was taken into account in the calculation. The possible contribution due to the formation of short range ordered structure is also discussed, with the conclusion that the decrease in SFE with increasing aluminium add...
87 CitationsSource
#1S. L. Semiatin (FFO: Wright-Patterson Air Force Base)H-Index: 78
#3Roger D. Doherty (Drexel University)H-Index: 40
The time for the static globularization of alpha lamellae in Ti-6Al-4V was predicted using analytical and finite-difference models based on the diffusion-controlled migration of the edges of remnant pancake-shaped particles. Similar to a previous two-dimensional analysis of the cylinderization of a semi-infinite, platelike second phase, the models quantified the influence of heat-treatment temperature, platelet thickness, and platelet diameter-to-thickness ratio on globularization kinetics. The ...
70 CitationsSource
#1Debes Bhattacharyya (OSU: Ohio State University)H-Index: 62
#2G.B. Viswanathan (OSU: Ohio State University)H-Index: 29
Last. Hamish L. Fraser (OSU: Ohio State University)H-Index: 73
view all 5 authors...
The present study has examined for α/β-Ti alloys the relationship between the morphology and crystallography of Widmanstatten plates of α-Ti in colonies within a prior grain of β-Ti. Thus, optical metallography, scanning electron microscopy and transmission electron microscopy have been used to characterize the morphological features of the microstructure, whereas orientation-imaging microscopy (OM) and transmission electron microscopy (TEM) have been employed to reveal crystallographic informat...
198 CitationsSource
#1S. Gourdet (Ecole nationale supérieure des mines de Saint-Étienne)H-Index: 2
#2Frank Montheillet (Ecole nationale supérieure des mines de Saint-Étienne)H-Index: 23
During continuous dynamic recrystallization (CDRX), which occurs in high stacking fault energy metals, new grains are formed by the progressive increase of low-angle boundary misorientations. A simple CDRX model is proposed, that deals with a set of “crystallites” delimited partly by low-angle (LABs) and partly by high-angle (HABs) boundaries. Strain hardening and dynamic recovery are described by the Laasraoui-Jonas equation, which has been modified to take HAB migration into account. Recovery ...
480 CitationsSource
Cited By22
#1Hamid Reza Javadinejad (HBNU: Hanbat National University)H-Index: 1
#2Giseung Shin (HBNU: Hanbat National University)H-Index: 1
Last. Jeoung Han Kim (HBNU: Hanbat National University)H-Index: 23
view all 7 authors...
Abstract Pack rolling is an effective process for manufacturing Ti-6Al-4V products, especially thin sheets; however, it tends to cause surface defects. Surface ridging is the most significant surface defect produced during the pack rolling of thin sheets. Hence, in this study, the effects of pack-rolling conditions on the origin of surface ridging on Ti–6Al–4V alloy surfaces were investigated using experimental and numerical techniques. Pack rolling was carried out at temperatures of 830, 860, 9...
#1Jakub Toman (University of Pittsburgh)H-Index: 6
#2Darren C. Pagan (Cornell University)H-Index: 14
Last. Markus Chmielus (University of Pittsburgh)H-Index: 9
view all 4 authors...
Abstract null null Additive manufacturing (AM) of magnetic shape-memory alloys (MSMAs) allows fuller use of geometry in the design of MSMA parts and avoids the segregation and high cost associated with single crystal production. While most research effort in AM of MSMAs pursues functional foams or polycrystals, epitaxial growth during liquid-phase AM may enable fully-dense single-crystalline MSMA parts, with associated availability of the full blocking stress. We melted a Ni51Mn24.4Ga24.6 single...
#1Shi-chen Sun (SDUT: Shandong University of Technology)H-Index: 1
#2Ertuan Zhao (SDUT: Shandong University of Technology)H-Index: 3
Last. Wenzhen Chen (HIT: Harbin Institute of Technology)H-Index: 15
view all 5 authors...
Abstract To investigate the precipitation behavior of silicide and evaluate the contribution of the reinforcement phase to the properties of titanium matrix composites, a TiB-reinforced high-temperature titanium matrix composite was prepared by vacuum induction melting and multi-directional forging. The microstructure of the resultant composite after multi-directional forging was composed of a spheroidized α-phase, uniformly-distributed TiB and dual-scale silicides. The precipitation of silicide...
5 CitationsSource
#1Qing Shan Liu (Beijing University of Technology)
#2Bo Long Li (Beijing University of Technology)H-Index: 9
Last. Zuo Ren Nie (Beijing University of Technology)H-Index: 11
view all 6 authors...
#1Maciej Motyka (Rzeszów University of Technology)H-Index: 11
#2Wojciech J. Nowak (Rzeszów University of Technology)H-Index: 12
Last. Witold Chrominski (Warsaw University of Technology)H-Index: 11
view all 4 authors...
The aim of the research was to investigate the microstructural changes caused by diffusion through interface between α and β titanium solid solutions. For this purpose, a diffusion couple composed of two single-phase titanium alloys—α type commercially pure (CP) titanium Grade 2 and near-β Ti-15V-3Al-3Cr-3Sn—was made by annealing at a temperature of 850 °C in an inert atmosphere. The performed heat treatment caused partial diffusion bonding (DB) where the α/β-interface was clearly visible. Based...
1 CitationsSource
#1Caiyou Zeng (The Welding Institute)H-Index: 1
Abstract The microstructure and corrosion fatigue behavior under artificial seawater environment of 100-mm-thick Ti–6Al–4V alloy joint via vacuum electron beam welding (EBW) was systematically characterized. Obvious microstructural heterogeneity along the transverse direction of as-welded joint was observed. Bimodal-phases microstructure of granular α colonies and β strips compose the microstructure of the base metal (BM). While the microstructure of fusion zone (FZ) comprises single-phase acicu...
#1Y.X. Zhou (Chongqing University)
#2Ke Wang (Chongqing University)
Abstract The near-α titanium alloy TA19 with three typical microstructures (lamellar, equaixed and bimodal microstructure) were compressed, accompanied by ex-situ observation on the slip trace and crack nucleation, which aimed to reveal the dependence of mechanical properties on microstructure based on analyzing the deformation mechanism. The results revealed that the lamellar microstructure had the lowest yield strength because of very large colony size. Meanwhile, although the equiaxed α grain...
6 CitationsSource
#1Guoming Zheng (NPU: Northwestern Polytechnical University)H-Index: 1
#2Xiaonan Mao (NU: Northeastern University)H-Index: 1
Last. Yongqiang ZhangH-Index: 1
view all 4 authors...
Abstract Ti6242S alloy bar with equiaxed microstructure and random textures was selected to investigate evolution of microstructure and texture during the process of forging bar into disk by isothermal constant speed hot compression test. Experimental investigation shows that αp grains experienced bend, rotation under prismatic slip system action and further separated into refined grains by dynamic recovery or dynamic recrystallization with the increase of strain. Sharp macrozones existed in Ti6...
7 CitationsSource
#1Shixing Huang (NU: Northeastern University)H-Index: 4
#2Yongqing Zhao (NU: Northeastern University)H-Index: 2
Last. Weiju JiaH-Index: 3
view all 6 authors...
Abstract Effects of Nb element partition on microstructure, tensile and impact properties of a near α Ti–4Nb alloy are studied by experimental and theoretical methods. Results of the BSE and EDS analysis reveal the partition of Nb element in α and β phase of Ti–4Nb alloy annealed at 750 °C, 800 °C and 830 °C, respectively. Microstructure, tensile and impact properties are distinctly affected by the partition of Nb element. β Phase containing more Nb element plays an important role to strengthen ...
10 CitationsSource
#1Entao Dong (USTB: University of Science and Technology Beijing)H-Index: 4
#2Wei Yu (USTB: University of Science and Technology Beijing)H-Index: 5
Last. Gaoxiang GongH-Index: 1
view all 5 authors...