Study on hot processing maps and deformation mechanisms of TC11 titanium alloy

Abstract The causes of plane crashes, stemming from the subcritical growth of fatigue cracks, are examined. It is found that the crashes occurred mainly because of the negligence of the defects arising in the course of secondary metalworking processes. It is shown that it is possible to prevent such damage, i.e. voids, wedge cracks, grain boundary cracks, adiabatic shear bands and flow localization, through the use of processing maps indicating the ranges in which the above defects arise and the ranges in which safe deformation mechanisms, such as deformation in dynamic recrystallization conditions, superplasticity, globularization and dynamic recovery, occur. Thanks to the use of such maps the processes can be optimized by selecting proper deformation rates and forming temperatures.

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Application of the Strain Compensation Model and Processing Maps for Description of Hot Deformation Behavior of Metastable β Titanium Alloy

Materials ◽

10.3390/ma14082021 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2021

Author(s):

Oleksandr Lypchanskyi ◽

Tomasz Śleboda ◽

Aneta Łukaszek-Sołek ◽

Krystian Zyguła ◽

Marek Wojtaszek

Keyword(s):

Titanium Alloy ◽

Strain Rate ◽

Flow Behavior ◽

Microstructural Analysis ◽

Calculated Data ◽

Processing Temperature ◽

Processing Maps ◽

Compression Tests ◽

Strain And Strain Rate ◽

Average Absolute Relative Error

The flow behavior of metastable β titanium alloy was investigated basing on isothermal hot compression tests performed on Gleeble 3800 thermomechanical simulator at near and above β transus temperatures. The flow stress curves were obtained for deformation temperature range of 800–1100 °C and strain rate range of 0.01–100 s−1. The strain compensated constitutive model was developed using the Arrhenius-type equation. The high correlation coefficient (R) as well as low average absolute relative error (AARE) between the experimental and the calculated data confirmed a high accuracy of the developed model. The dynamic material modeling in combination with the Prasad stability criterion made it possible to generate processing maps for the investigated processing temperature, strain and strain rate ranges. The high material flow stability under investigated deformation conditions was revealed. The microstructural analysis provided additional information regarding the flow behavior and predominant deformation mechanism. It was found that dynamic recovery (DRV) was the main mechanism operating during the deformation of the investigated β 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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Rolling reduction - dependent deformation mechanisms and tensile properties in a β titanium alloy

Journal of Material Science and Technology ◽

10.1016/j.jmst.2021.05.071 ◽

2021 ◽

Author(s):

Zhaoxin Du ◽

Qiwei He ◽

Ruirun Chen ◽

Fei Liu ◽

Jingyong Zhang ◽

...

Keyword(s):

Titanium Alloy ◽

Tensile Properties ◽

Rolling Reduction ◽

Deformation Mechanisms

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Simulation of Deformation Behavior and Microstructure Evolution during Hot Forging of TC11 Titanium Alloy

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.385.449 ◽

2018 ◽

Vol 385 ◽

pp. 449-454 ◽

Cited By ~ 3

Author(s):

Artem Alimov ◽

Dmitry Zabelyan ◽

Igor Burlakov ◽

Igor Korotkov ◽

Yuri Gladkov

Keyword(s):

Titanium Alloy ◽

Microstructure Evolution ◽

Technology Development ◽

Hot Forging ◽

Industrial Case Study ◽

Aerospace Applications ◽

Heating And Cooling ◽

Tc11 Titanium Alloy ◽

Kinetics Of

Finite element method is the most powerful tool for development and optimization of the metal forming processes. Analysis of titanium alloy critical parts should include the prediction of microstructure since their mechanical and technological properties essentially depend on the type and parameters of the microstructure. The technological process of parts production for aerospace applications is multi-operational and consists of deformation, heating and cooling stages. Therefore, it is necessary to simulate the microstructure evolution to obtain high quality parts. In presented paper FE simulation coupled with microstructure evolution during hot forging of TC11 titanium alloy has been performed by QForm FEM code. Constitutive relationships, friction conditions and microstructure evolution model have been established using the experiments. The kinetics of phase transformations has been described by the Johnson-Mehl-Avrami-Kolmogorov (JMAK) phenomenological model. The approach is illustrated by industrial case study that proved its practical applicability and economic advantages for technology development of titanium alloy critical parts.

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