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journal homepage: www.elsevier.com/locate/jmrt

Original Article

Microstructural evolution and mechanical

properties of a novel biomedical Tie6Zre4Fe alloy
during solution and aging treatment

Peng Qi a, Bolong Li a,*, Wu Wei a, Jimin Chen a,b, Tongbo Wang c,

Hui Huang a,**, Kunyuan Gao a, Shengping Wen a, Xiaolan Wu a, Li Rong a,
Xiangyuan Xiong a, Wenjun Wu d, Lian Zhou a,b,d, Zuoren Nie a
a
Faculty of Materials and Manufacturing, Key Laboratory of Advanced Functional Materials, Education Ministry of
China, Beijing University of Technology, Beijing, 100124, China
b
Beijing Engineering Research Center of 3D Printing for Digital Medical Health, Beijing University of Technology,
Beijing, 100124, China
c
Chinalco Science and Technology Institute Co., LTD, Beijing, 102209, China
d
Northwest Institute for Nonferrous Metal Research, Xi'an, 710016, China

article info abstract

Article history: Microstructural evolution and its effect on microhardness and Young's modulus of Tie6Zr
Received 4 July 2022 e4Fe alloy solution and aging treated at different temperatures were studied. The a phase
Accepted 14 September 2022 transformed into b phase completely at 860
C, meanwhile, the athermal u phase was found
Available online 20 September 2022 at 860
C and it resulted in a higher Young's modulus. The u phase content increased from
250
C to 400
C, and the content decreased with further increase of aging temperature, there
Keywords: were only a phase and b phase at 600
C. The phase transformation sequence was
Tie6Zre4Fe alloy b / u þ b / u þ a þ b / a þ b during aging treatment. The microhardness increased from 315
Solution treatment HV to 492 HV due to the element solution strengthening and phase transformation
Aging treatment strengthening. The peak microhardness of Tie6Zre4Fe alloy aged at 400
C reached 652 HV.
Microstructure The formation of u phase resulted in the increase of microhardness and Young's modulus in
Mechanical properties Tie6Zre4Fe alloy.
© 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC
BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

biocompatibility, and higher corrosion resistance than

1. Introduction biomedical stainless steel and biomedical CoeCr alloys [1,2]. In
general, to obtain the combination of lower Young's modulus
Near b titanium (Ti) alloys have been widely used as biomedical and higher microhardness of Ti alloys, the alloy composition
implant materials due to the lower Young's modulus, better design and microstructure regulation was used by researchers

* Corresponding author.
** Corresponding author.
E-mail addresses: blli@bjut.edu.cn (B. Li), huanghui@bjut.edu.cn (H. Huang).
https://doi.org/10.1016/j.jmrt.2022.09.063
2238-7854/© 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://
creativecommons.org/licenses/by-nc-nd/4.0/).
430 j o u r n a l o f m a t e r i a l s r e s e a r c h a n d t e c h n o l o g y 2 0 2 2 ; 2 1 : 4 2 9 e4 3 7

[3e5]. Firstly, the Fe element has high stability of the b phase, athermal and isothermal u phases influence the strength-to-
and the addition of Zr element can improve the corrosion modulus ratio greatly [12]. In general, the crystal structures
resistance for Ti alloys [6e8]. Meanwhile, the Fe element and Zr of athermal and isothermal u phases are consistent, the
element have a strong solid solution strengthening effect in the biggest difference between them is the different formation
Ti alloy [9,10]. The Zr and Fe elements in the alloy are non- conditions. The athermal u precipitates have typically been
allergenic and non-toxic, and the addition of Fe elements can observed in alloys quenched from the high-temperature b
also decrease the cost. In order to reduce the difficulties of phase field. The isothermal u precipitates have been postu-
process and cost, the novel near-b Tie6Zre4Fe alloy was lated to form via a thermally activated process involving
designed on the basis of biomedical application, preparation, diffusion-based compositional partitioning [18].
element composition, and low-cost. The previous works found According to the present research, the desired functional-
that this alloy exhibited excellent mechanical properties and ities and mechanical properties were obtained by heat treat-
corrosion resistance [11]. ment. The novel Tie6Zre4Fe alloy is a biomedical b-Ti alloy,
In general, the mechanical property of Ti alloy depends on and the microstructure can be regulated by solution and aging
the area fraction and scale of a, b, a0 , a'' and u phases [12,13]. treatment [19]. Up to now, little investigation of heat treatment
Solution and aging treatment processing is usually used to on this novel Tie6Zre4Fe alloy has not been reported yet to the
obtain the desired functionalities and mechanical properties best of our knowledge. Therefore, in this paper, the micro-
for Ti alloys by controlling phases [14]. Up to now, researchers structural evolution and its effect on microhardness and
had to pay much attention to controlling microstructure by Young's modulus of novel Tie6Zre4Fe alloy during solution
heat treatment to improve the mechanical properties of Ti and aging treatment have been investigated. The influence of
alloy. The microstructural tailoring and mechanical proper- solution and aging temperature on the evolution of phase
ties of a new near b Ti-5321 alloy with various heat treatments composition and phase transformation sequence is analyzed,
were studied, the alloy got an excellent balance of high and the relationship between microstructure and microhard-
strength and good ductility by the heat treatment, depending ness, Young's modulus in Tie6Zre4Fe alloy is also discussed.
on the change of volume fraction and size of a phase [15]. The
Tie15Zr-xMo alloys obtained a0 , a0 þb and b phase micro-
structures for biomedical applications by low-temperature 2. Experimental
heat treatments [16]. Sang Won Lee et al. [17] studied the ef-
fect of solution treatment and aging conditions on tensile 2.1. Materials and characterization
properties of TieAleFeeSi alloy. They found that solution
temperature affected the stability of the b phase due to the Fe The Tie6Zre4Fe alloy was prepared from Ti (purity ¼ 99.90 wt.%),
partitioning, and the various aging temperature determined Zr (purity ¼ 99.90 wt.%) and Fe (purity ¼ 99.95 wt.%). Tie6Zre4Fe
the phase transformation. The microhardness and Young's alloy ingot was re-melted three times in a vacuum arc remelting
modulus of Ti alloy treated by different heat treatments are furnace to improve chemical homogeneity. The chemical com-
different due to the change of phase compositions, the positions of the Tie6Zre4Fe sample were analyzed by X-ray

Fig. 1 e Microstructure of the as-cast Tie6Zre4Fe alloy: (a) SEM micrograph, (b) TEM image, (c) and (d) selected area
diffraction patterns.
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Fig. 2 e Schematic illustration of different heat treatment processes: (a) solution treatment process, (b) aging treatment
process.

fluorescence (XRF-1800) analysis and OxygeneNitrogeneHydr- was tested nine times. The Young's modulus of Tie6Zre4Fe
ogen Analyzer, (Zr 5.42 wt.%, Fe 4.00 wt.%, O 610 ppm, N 100 ppm, alloy was tested by using TI-950 Nanoindentation system
H 20 ppm, Ti: Bal). (Hysitron, MA, USA) with a diamond tip and Berkovich ge-
X-ray diffraction (XRD, and XRD-7000) with Cu Ka radiation ometry, and each test data was tested nine times.
was used to examine the phase analysis of the Tie6Zre4Fe
samples. The samples were cut to square samples (10m-
m  10mm  5 mm) and mechanically ground and polished. 3. Results
Surfaces of samples were etched for 90 s using a solution of 6
vol.% HClO4 in 94 vol.% CH3COOH for microstructural obser- 3.1. Microstructural evolution during solution treatment
vations. The microstructure of the sample was analyzed by FEI
Quanta 650-FEG scanning electron microscope (SEM). Then the To study the effect of solution temperature on the volume
volume fraction of a phase was measured using Image-Pro Plus fraction and morphology of a phase, the SEM micrographs of
6.0 software (IPP 6.0). The transmission electron microscopy Tie6Zre4Fe alloy were analyzed after solution treated at
(TEM) samples were prepared by mechanical polishing and different temperatures from 720
C to 860
C, as shown in Fig. 3.
then a twin-jet electro-polishing technique in a solution of 6 It shows that the volume fraction of a phase decreases from
vol.% perchloric acids, 59 vol.% methanol and 35 vol.% n-butyl 37% to 2% gradually with increasing the solution temperature
alcohol at 30
C. TEM observations were carried out using JEOL from 720
C to 840
C, and there is no a phase in the Tie6Zre4Fe
JEM-2100F. Fig. 1a shows the SEM micrograph of as-cast alloy solution treated at 860
C. It indicated that the trans-
Tie6Zre4Fe alloy, which mainly includes a phase and b formation of a phase in Tie6Zre4Fe alloy was highly sensitive
phase. The TEM micrograph of as-cast Tie6Zre4Fe alloy shows to solution temperature. Meanwhile, lamellar and rod-shaped a
that it mainly includes a phase and b phase, as shown in Fig. 1b. phase was distributed in the microstructure of Tie6Zre4Fe
The selected diffraction pattern also shows that the as-cast alloy solution treated at 720
Ce760
C. The volume fraction of
alloy is mainly composed of a and b phases, as shown in the lamellar a phase decreased with the increase of solution
Fig. 1c and d. The samples were cut into square samples temperature from 720
C to 760
C, as shown in Fig. 3aec. The
(10mm  10mm  5 mm) for heat treatment. Tie6Zre4Fe alloy solution treated at 780
Ce840
C mainly
According to the calculation of the theoretical phase included a rod-shaped a phase, and the volume fraction
transition point [20], the phase transition temperature of the decreased with the increase of solution temperature, as shown
Tie6Zre4Fe alloy was about 807
C. Based on the theoretical in Fig. 3deg. The change of lamellar and rod-shaped a phase
phase transition temperature and aging heat treatment pro- indicated that the rod-shaped a phase was more stable than the
cess of near b titanium [12,15], the different heat treatment lamellar a phase in Tie6Zre4Fe alloy.
processes of Tie6Zre4Fe alloy were designed, as shown in The number in the top right corner shows the volume
Fig. 2. The specimens were solution treated at different tem- fraction of the primary a phase in the b matrix. In order to
peratures, followed by water quenching. Then, the as- further investigate the change of phase in Tie6Zre4Fe alloy,
solutionized samples were aged at different temperatures the TEM micrographs of Tie6Zre4Fe alloy solution treated at
respectively, followed by air cooling. different temperatures were analyzed, as shown in Fig. 4. The
Tie6Zre4Fe alloy solution treated at 720
C mainly included a
2.2. Tests of properties phase and b phase, as shown in Fig. 4a. Under solution treated
at 860
C, apart from the b phase, it can be found that amounts
Microhardness of Tie6Zre4Fe alloy was tested using a Vickers' of athermal u phase are distributed within the b matrix, as
hardness tester operated at a load of 300 gf and each test data shown in Fig. 4c,d.
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Fig. 3 e SEM micrographs of Tie6Zre4Fe alloy solution treated at different temperatures: (a) 720
C, (b) 740
C, (c) 760
C, (d)
780
C, (e) 800
C, (f) 820
C, (g) 840
C, (h) 860
C.

3.2. Microstructural evolution during aging treatment temperatures, the secondary a phase was hardly distin-
guished from SEM observation.
The influences of aging temperature on the microstructural In order to further understand the effect of aging temper-
evolution of Tie6Zre4Fe alloy were evaluated. Fig. 5 shows the ature on the phase transformation of Tie6Zre4Fe alloy, the
SEM micrographs of Tie6Zre4Fe alloys aging treated at TEM results of the alloy after aging at 250
C, 400
C, 500
C,
different temperatures. As shown in Fig. 5aee, there is no a and 600
C were observed, as shown in Fig. 7. In the TEM
phase in the Tie6Zre4Fe alloy aging treated before 450
C. bright-field image of Fig. 7a, there was u phase in the
With the increase of aging temperature from 450
C to 600
C, Tie6Zre4Fe alloy during aging at 250
C. u phases were
there was formation of phase in Tie6Zre4Fe alloy, and the distributed uniformly in b matrix aging treated at 400
C, as
size of phase precipitates is very small. Furthermore, the shown in Fig. 7b. The intensity of peaks for u phase was ob-
phases in Tie6Zre4Fe alloy were analyzed by XRD pattern tained at 400
C. With the increase of aging temperature, the
after different aging treatments, as shown in Fig. 6. The XRD size of the isothermal u phase increased, as shown in Fig. 7b, e
patterns revealed that the phase changed from b phase into a and h. It was clear to see that a large amount of a phase was
phase and finally became aþb microstructure. But there was precipitated in b matrix aged at 500
C and the size of the
only a peak of b phase in Tie6Zre4Fe alloy aging treated before isothermal u phase increased. While, there was no isothermal
450
C due to little precipitate phase. When aged at different u phase in the Tie6Zre4Fe alloy aged at 600
C, as shown in

Fig. 4 e TEM micrographs of Tie6Zre4Fe alloy solution treated at different temperatures: (a) 720
C and (b) 860
C bright-field
image, (c) 860
C electronic diffraction pattern, (d) 860
C dark field image.
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Fig. 5 e SEM micrographs of Tie6Zre4Fe alloy aging treated at different temperatures: (a) 250
C, (b) 300
C, (c) 350
C, (d)
400
C, (e) 450
C, (f) 500
C, (g) 550
C, (h) 600
C.

Fig. 7j, m). There were only a phase and b phase, and the size and aging temperature. The microstructure change in
of a phase increased. Meanwhile, the elliptical a phase was morphology, size-scale, and distribution of a phase and u phase
changed to an elongated a phase, as shown in Fig. 7g, j). have dramatically affected mechanical properties after different
solution and aging processes. Based on the results, the effects of
3.3. Mechanical properties after solution and aging heat treatment on the microstructure and mechanical proper-
treatment ties of the novel Tie6Zre4Fe alloy are discussed.

In order to study the effect of solution and aging treatment on 4.1. Effect of heat treatment on microstructural
the mechanical properties, the microhardness of Tie6Zre4Fe evolution of Tie6Zre4Fe alloy
alloy heat-treated at various temperatures was measured, as
shown in Fig. 8 a and b. The microhardness of Tie6Zre4Fe In general, the b phase in Ti alloy can be considered stable
alloy increased with increasing solution temperature, the during water quenching when the Mo equivalence ([Mo]eq) is
value of microhardness increased from 264 HV for a cast state greater than 10 [21]. According to Equation (1), the [Mo]eq of the
to 315 HV for a solution state of 720
C. Furthermore, the novel Tie6Zre4Fe alloy is 10, therefore the b phase can be
microhardness increased from 315 HV to 482 HV with stable at room temperature during water quenching [22]. The
increasing solution temperature from 720
C to 820
C, then it SEM micrographs of the Tie6Zre4Fe alloy solution treated at
increased slowly with increase of solution temperature, 860
C under water quenching showed that the b phase was
finally, the microhardness of Tie6Zre4Fe alloy remained sta- stable. According to the results of SEM micrographs, the b-trans
ble values until 860
C. Consequently, the hardness increases temperature of the novel Tie6Zre4Fe alloy was near 860
C.
rapidly and then keeps almost stable with increasing solution The b-trans temperature of the Tie6Zre4Fe alloy was lower
temperature. The microhardness increased from 520 HV to than the a-Ti alloy due to the b stabilization of Fe element.
652 HV with increasing aging temperature from 250
C to
400
C and then decreased from 652 HV to 473 HV with further
increasing aging temperature from 400
C to 600
C, as shown
in Fig. 8b. Meanwhile, the peak microhardness of Tie6Zre4Fe
alloy aging treated at 400
C reaches up to 652 HV, which is
higher than most existing alloys [19].
The Young's modulus of Tie6Zre4Fe alloy was measured
after the different heat treatment processes, as shown in
Fig. 8c. Young's modulus is 90 GPa in as-cast state, 98 GPa in
solution treatment of 860
C, and 134 GPa in aging treatment of
400
C. The change of mechanical properties of Tie6Zre4Fe
alloy was greatly influenced by the different heat treatments.

4. Discussions

The experimental results indicate that the morphology, size-

scale, and distribution of a and u phase in the novel Fig. 6 e XRD patterns of Tie6Zre4Fe alloy aging treated at
Tie6Zre4Fe alloy were significantly influenced by the solution different temperatures.
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Fig. 7 e TEM micrographs of Tie6Zre4Fe alloy aging treated at different temperatures: (a, b, c) 250
C, (d, e, f) 400
C, (g, h, i)
500
C, (j, k, m) 600
C. (a, d, g, j) bright field image, (b, e, h, k) dark field image, (c, f, i, m) selected area diffraction pattern.

elements of b phase higher than the critical content bc, the b

phase is retained in a metastable state by quenching (noted
[Mo]eq ¼ [Mo] þ 0.2[Ta] þ 0.28[Nb] þ 0.4[W] þ 0.67[V] þ 1.25
bm). The bm phase can partially transform into athermal u
[Cr] þ 1.25[Ni] þ 1.7[Mn] þ 1.7[Co] þ 2.5[Fe] (1)
phase, during the quenching process. According to pseudo-
binary diagram of titanium with the decomposition products
The SEM micrographs of Tie6Zre4Fe alloy solution treated
of the b phase studied by P. Laheurte [29], the critical concen-
at 860
C suggested that all phases were single b phases.
tration bc of Fe in Ti alloy is about 4 wt.%. The formation of the
However, the TEM micrograph of Tie6Zre4Fe alloy solution
athermal u phase in Tie6Zre4Fe alloy will improve the
treated at 860
C also contained a low volume fraction of an
microhardness and causes the increase of Young's modulus.
extremely small u phase. D. De. Fontaine et al. found that u
The u phase can form at a low aging temperature, termed
phase can form upon quenching from the b-phase field, termed
isothermal u phase [30,31]. In addition, the size of u phase in
the athermal u phase [23]. The athermal u phase trans-
Tie6Zre4Fe alloy treated at aging treatment is larger than that
formation occurring during quenching also has been found in
treated at solution treatment. Meanwhile, the isothermal u
many other metastable b type titanium alloys [24e26]. Ac-
phase increased with an aging temperature from 250
C to
cording to the molecular orbital theory (Bo-Md) developed by
400
C and then decreased with a further increase in tem-
Morinaga et al. [27,28], the average Bo is 2.795 and the average
perature. It suggests that the isothermal u phase is acceler-
Md is 2.410 in Tie6Zre4Fe alloy [11], the phase mainly includes
ated with the increasing aging temperature. The u phase in
b and u phase. In addition, for a concentration of the stabilizing
Tie6Zre4Fe alloy was unstable and can dissolve and
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Fig. 8 e Mechanical properties of Tie6Zre4Fe alloy with different heat treatment processes: (a) microhardness of solution
treated at different temperatures, (b) microhardness of aging treated at different temperatures, (c) Young's modulus.

transform to a phase during aging, as reported in the literature treatments. It is reported that Young's modulus of a, b, a0 , a''
[24]. The TEM micrographs of Tie6Zre4Fe alloy show that the and u phase in Ti alloy is u>a'>a>b>a'' [33]. The Tie6Zre4Fe
transformation sequence of phase is b/uþb/uþaþb/aþb alloy solution treated at 860
C had a higher Young's modulus
during aging treatment. The transformation of various phases than that as-cast state. The increase of b phase and decrease
in Tie6Zre4Fe alloy can be obtained by the adjustment of of a phase cannot reduce Young's modulus of the Tie6Zre4Fe
aging treatment. alloy at solution state due to the formation of u phase during
rapid cooling. The u phase of Tie6Zre4Fe alloy aging treated
4.2. Effect of heat treatment on mechanical properties of at 400
C reached the peak value, which resulted in the highest
Tie6Zre4Fe alloy Young's modulus of Tie6Zre4Fe alloy.

The microhardness of Tie6Zre4Fe alloy increased with the

increase of solution temperature, as shown in Fig. 8a. It is 5. Conclusions
reported that the microhardness of a, b, a0 , a'' and u phase in
titanium alloy is u>a'>a>b>a'' [24]. The microhardness of the In this study, the microstructural evolution and its effect on
alloy solution treated at different temperatures will be vari- microhardness and Young's modulus of a novel biomedical
ated due to the change of phase in Tie6Zre4Fe alloy. However, Tie6Zre4Fe alloy solution treated and aging treated at
the area fraction of a phase decreased and the content of b different temperatures were investigated. The main conclu-
phase increased with the increase of solution temperature, as sions are summarized as below:
shown in Fig. 3. According to the difference in microhardness
of a and b phases, the microhardness of Tie6Zre4Fe alloy 1) The volume fraction and morphology of a phase are highly
should be decreased with the increase of solution tempera- sensitive to solution temperature. The volume fraction of a
ture. Nevertheless, according to Fig. 4, there was the forma- phase decreased from 37% to 0% gradually with increasing
tion of u phase, and it may be one of the reasons for increasing the solution temperature from 720
C to 860
C. The athe-
in microhardness. Meanwhile, the Fe element and Zr element rmal u phase formed in the Tie6Zre4Fe alloy solution
have a strong solid solution strengthening effect in the Ti alloy treated at 860
C.
[32]. Consequently, the increase of microhardness is attrib- 2) The precipitation of a phase and u phase was greatly
uted to the strengthening of the solution element and u phase. influenced by the aging temperature. The phase trans-
The Tie6Zre4Fe alloy went through under-aging, peak- formation sequence in Tie6Zre4Fe alloy is
aging, and over-aging stages during aging treatments at b/u þ b/u þ a þ b/a þ b during aging treatment.
different temperatures. The microhardness of Tie6Zre4Fe 3) The solution and aging temperature influenced the
alloy increased with an aging temperature from 250
C to microhardness of Tie6Zre4Fe alloy due to the change of a
400
C and then decreased with the increase of aging tem- phase and u phase. The combined effect of solution
perature, as shown in Fig. 8b. According to the phase precip- strengthening and phase transformation strengthening
itation (seen in Figs. 5 and 7), there was the formation of the improves the microhardness of Tie6Zre4Fe alloy after so-
isothermal u phase from 250
C to 400
C, which was the main lution treatment. After solution treated at 860
C and aging
factor of aging hardening. Then the microhardness of treated at 400
C, the microhardness of Tie6Zre4Fe alloy
Tie6Zre4Fe alloy decreased with the increase of aging tem- reaches up to 652 HV.
perature due to the growth of a phase and decrease of u phase 4) The phase composition strongly affects Young's modulus,
content. The age-hardening behavior of Tie6Zre4Fe alloy and the formation of u phase is the main factor for the
(seen in Fig. 8) was consistent with such a change in the vol- increase of Young's modulus in Tie6Zre4Fe alloy. The
ume fraction of u phase and a phase. phase composition of biomedical titanium needs to be
The Young's modulus of Tie6Zre4Fe alloy in different regulated and controlled for getting ideal properties for
states is changed due to the phase compositions at different biomedical application.
436 j o u r n a l o f m a t e r i a l s r e s e a r c h a n d t e c h n o l o g y 2 0 2 2 ; 2 1 : 4 2 9 e4 3 7

Mater Sci Eng A Struct 2022;843:143053. https://doi.org/

Declaration of Competing Interest 10.1016/j.msea.2022.143053.
[10] Gao Y, Yang L, Fan QB, Lei W, Chen K, Zhu XJ, et al. Effect of
The authors declare that they have no known competing Fe content on microstructure and hardness of Ti-4.5Mo-5Al-
financial interests or personal relationships that could have 1.8Zr-2.5Cr-1.1Sn titanium alloy based on high-throughput
diffusion couple. Mater Sci Eng A Struct 2022;842:143089.
appeared to influence the work reported in this paper.
https://doi.org/10.1016/j.msea.2022.143089.
[11] Qi P, Li BL, Wang TB, Zhou L, Nie ZR. Microstructure and
properties of a novel ternary Ti-6Zr-xFe alloy for biomedical
Acknowledgment applications. J Alloys Compd 2020;854:157119. https://doi.org/
10.1016/j.jallcom.2020.157119.
This work was supported by Beijing Natural Science Founda- [12] Xu YF, Liu HQ, Zhang S, Xiong HQ. Effect of duplex aging on
tion [Grant No. 2202007], National Natural Science Foundation microstructural and mechanical behavior of a new b-Ti alloy
for biomedical applications. J Mater Res Technol
of China [Grant No. 91860113, Grant No. 51621003], National
2022;18:2870e84. https://doi.org/10.1016/j.jmrt.2022.03.174.
Key Research and Development Program of China (2021YF-
[13] Fu Y, Xiao WL, Wang JS, Zhao XQ, Ma CL. Mechanical
B3704205), General Program of Science and Technology properties and deformation mechanisms of Ti-15 Nb-5Zr-
Development Project of Beijing Municipal Education Com- 4Sn-1Fe alloy with varying a phase fraction. J Alloys Compd
mission (KM 202110005010), QiHang Programme” for Faculty 2022;898:162816. https://doi.org/10.1016/
of Materials and Manufacturing BJUT (QH202203) and the j.jallcom.2021.162816.
Beijing Laboratory of Metallic Materials and Processing for [14] Banerjee D, Williams J. Perspective on titanium science and
technology. Acta Mater 2013;61:844e79. https://doi.org/
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