Constitutive equation and hot processing map of TA15 titanium alloy

The hot deformation behavior and hot rolling based on the hot processing map of a nano-Y2O3 addition near-α titanium alloy were investigated. The isothermal compression tests were conducted at various deformation temperatures (950⁠–1070 °C) and strain rates (0.001–1 s−1), up to a true strain of 1.2. The flow stress was strongly dependent on deformation temperature and strain rate, decreasing with increased temperature and decreased strain rate. The average activation energy was 657.8 kJ/mol and 405.9 kJ/mol in (α + β) and β region, respectively. The high activation energy and peak stress were contributed to the Y2O3 particles and refractory elements comparing with other alloys and composites. The deformation mechanisms in the (α + β) region were dynamic recovery and spheroidization of α phase, while the β phase field was mainly controlled by the dynamic recrystallization and dynamic recovery of β grains. Moreover, the constitutive equation based on Norton–Hoff equation and hot processing map were also obtained. Through the optimal processing window determined by the hot processing map at true strains of 0.2, 0.4 and 0.6, the alloy sheet with multi-pass hot rolling (1050 °C/0.03–1 s−1) was received directly from the as-cast alloy. The ultimate tensile strength and yield strength of the alloy sheet were 1168 MPa and 1091 MPa at room temperature, and 642 MPa and 535 MPa at 650 °C, respectively, which performs some advantages in current research.

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Constitutive Model Prediction and Flow Behavior Considering Strain Response in the Thermal Processing for the TA15 Titanium Alloy

Materials ◽

10.3390/ma11101985 ◽

2018 ◽

Vol 11 (10) ◽

pp. 1985 ◽

Cited By ~ 4

Author(s):

Jiang Li ◽

Fuguo Li ◽

Jun Cai

Keyword(s):

Titanium Alloy ◽

Flow Stress ◽

Constitutive Equation ◽

Flow Behavior ◽

Strain Effect ◽

Absolute Relative Error ◽

Average Absolute Relative Error ◽

Ta15 Titanium Alloy ◽

Measured Stress ◽

The Impact

To investigate the flow stress, microstructure, and usability of TA15 titanium alloy, isothermal compression was tested at 1073–1223 K and strain rates of 10, 1, 0.1, 0.01, and 0.001 s−1, and strain of 0.9. The impact of strain and temperature on thermal deformation was investigated through the exponent-type Zener–Hollomon equation. Based on the influence of various material constants (including α, n, Q, and lnA) on the TA15 titanium alloy, the strain effect was included in the constitutive equation considering strain compensation, which is presented in this paper. The validity of the proposed constitutive equation was verified through the correlation coefficient (R) and the average absolute relative error (AARE), the values of which were 0.9929% and 6.85%, respectively. Research results demonstrated that the strain-based constitutive equation realizes consistency between the calculated flow stress and the measured stress of TA15 titanium alloy at high temperatures.

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Removal mechanism of surface cleaning on TA15 titanium alloy using nanosecond pulsed laser

Optics & Laser Technology ◽

10.1016/j.optlastec.2021.106998 ◽

2021 ◽

Vol 139 ◽

pp. 106998

Author(s):

Zhichao Li ◽

Donghe Zhang ◽

Xuan Su ◽

Shirui Yang ◽

Jie Xu ◽

...

Keyword(s):

Titanium Alloy ◽

Pulsed Laser ◽

Surface Cleaning ◽

Removal Mechanism ◽

Nanosecond Pulsed Laser ◽

Ta15 Titanium Alloy

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Hot Deformation Behavior and Processing Maps of a New Ti-6Al-2Nb-2Zr-0.4B Titanium Alloy

Materials ◽

10.3390/ma14092456 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2456

Author(s):

Zhijun Yang ◽

Weixin Yu ◽

Shaoting Lang ◽

Junyi Wei ◽

Guanglong Wang ◽

...

Keyword(s):

Titanium Alloy ◽

Flow Stress ◽

Constitutive Equation ◽

Deformation Mechanism ◽

Power Dissipation ◽

Hot Deformation ◽

Dissipation Rate ◽

Dynamic Recovery ◽

Processing Maps ◽

Temperature Range

The hot deformation behaviors of a new Ti-6Al-2Nb-2Zr-0.4B titanium alloy in the strain rate range 0.01–10.0 s−1 and temperature range 850–1060 °C were evaluated using hot compressing testing on a Gleeble-3800 simulator at 60% of deformation degree. The flow stress characteristics of the alloy were analyzed according to the true stress–strain curve. The constitutive equation was established to describe the change of deformation temperature and flow stress with strain rate. The thermal deformation activation energy Q was equal to 551.7 kJ/mol. The constitutive equation was ε ˙=e54.41[sinh (0.01σ)]2.35exp(−551.7/RT). On the basis of the dynamic material model and the instability criterion, the processing maps were established at the strain of 0.5. The experimental results revealed that in the (α + β) region deformation, the power dissipation rate reached 53% in the range of 0.01–0.05 s−1 and temperature range of 920–980 °C, and the deformation mechanism was dynamic recovery. In the β region deformation, the power dissipation rate reached 48% in the range of 0.01–0.1 s−1 and temperature range of 1010–1040 °C, and the deformation mechanism involved dynamic recovery and dynamic recrystallization.

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Microstructure evolution of the transitional region in isothermal local loading of TA15 titanium alloy

Materials Science and Engineering A ◽

10.1016/j.msea.2010.12.006 ◽

2011 ◽

Vol 528 (6) ◽

pp. 2694-2703 ◽

Cited By ~ 21

Author(s):

X.G. Fan ◽

P.F. Gao ◽

H. Yang

Keyword(s):

Titanium Alloy ◽

Microstructure Evolution ◽

Transitional Region ◽

Local Loading ◽

Ta15 Titanium Alloy

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Study on hot deformation behaviour of 316LN austenitic stainless steel based on hot processing map

Materials Science and Technology ◽

10.1179/1743284712y.0000000083 ◽

2013 ◽

Vol 29 (1) ◽

pp. 24-29 ◽

Cited By ~ 13

Author(s):

X G Liu ◽

H P Ji ◽

H Guo ◽

M Jin ◽

B F Guo ◽

...

Keyword(s):

Stainless Steel ◽

Austenitic Stainless Steel ◽

Hot Deformation ◽

Processing Map ◽

Deformation Behaviour ◽

Hot Processing Map ◽

Hot Deformation Behaviour

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Fractal studies on primary phase morphology of TA15 titanium alloy after hot compressive deformation

Journal of Shanghai Jiaotong University (Science) ◽

10.1007/s12204-011-1157-9 ◽

2011 ◽

Vol 16 (3) ◽

pp. 343-346

Author(s):

Xia-wei Yang ◽

Jing-chuan Zhu ◽

Zhong-hong Lai ◽

Yong Liu ◽

Jia-jun Zhan

Keyword(s):

Titanium Alloy ◽

Primary Phase ◽

Phase Morphology ◽

Compressive Deformation ◽

Ta15 Titanium Alloy

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The Optimal Selection of Extrusion Parameters of As-Cast TC27 Titanium Alloy Based on Processing-Map

Materials Science Forum ◽

10.4028/www.scientific.net/msf.898.1134 ◽

2017 ◽

Vol 898 ◽

pp. 1134-1139

Author(s):

Xue Fei Li ◽

Ai Xue Sha ◽

Xu Huang ◽

Li Jun Huang

Keyword(s):

Titanium Alloy ◽

Flow Stress ◽

Strain Rate ◽

Processing Map ◽

True Strain ◽

Great Influence ◽

Stable Condition ◽

Dynamic Materials ◽

Dynamic Materials Model ◽

Selection Of

The hot deformation behavior of TC27 titanium alloy at the temperatures of 900-1150 °C and the strain rate of 0.01-10 s-1, the height reduction of 70%, was investigated in the isothermal compression test to identify the optimal extrusion parameters. The processing-map of TC27 titanium alloy was constructed based on dynamic materials model (DMM) and principle of Prasad*s instability. The conclusion shows that temperature and strain rate of deformation had a great influence on flow stress. At the beginning of deformation, the flow stress increased quickly with the augment of true strain and decreased slowly after flow stress reaching to the maximum value. Finally, flow stress tended to relatively stable condition. The flow stress decreased with the increase of temperature and increased with the increase of strain rate. The TC27 titanium alloy was sensitive to temperature and strain rate. Processing-map exhibited two peak efficiencies of power dissipation; one peak was 49% at 900°C/0.01 s-1, which dynamic recovery occured. The other peak was also 49% at 1050 °C /0.01s-1, which dynamic recrystallization occured in the domain. Besides, there were two instability areas in the processing-map which should be avoided during the extrusion. Therefore, in order to obtain the satisfactory properties, the parameters that 1050 °C and 0.01 s-1 were selected in the extrusion.

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