Dynamic Tensile Behavior and Constitutive Modeling of TC21 Titanium Alloy

Abstract

The dynamic tensile behaviors of a newly developed Ti-6Al-2Sn-2Zr-3Mo-1Cr-2Nb-Si alloy (referred as TC21 in China) over a wide range of strain rates from quasi-static to dynamic regimes (0.001–1 200 s⁻¹) at different temperatures were experimentally investigated. A split Hopkinson tension bar apparatus and a static material testing system were utilized to study the stress-strain responses under uniaxial tension loading condition. The experimental results indicate that the tensile behavior of TC21 titanium alloy is dependent on the strain rate and temperature. The values of initial yield stress increase with increasing strain rate and decreasing temperature. The effects of strain rate and temperature on the initial yield behavior are estimated by introducing two sensitivity parameters. The phenomenological-based constitutive model, Johnson-Cook model, is suitably modified to describe the rate-temperature dependent constitutive behavior of TC21 titanium alloy. It is observed that the modified model is in good agreement with the experimental data subjected to the investigated range of strain rates and temperatures.

Keywords

two-phase titanium alloy / dynamic tensile behavior / rate-temperature sensitivity / constitutive modeling

References

[1] Gysler A, LüTjering G. Influence of Test Temperature and Microstructure on the Tensile Properties of Titanium Alloys[J]. Metall. Trans. A, 1982, 13(8): 1 435-1 443.

[2] Reed-Hill R E, Iswaran C V, Kaufman M J. An Analysis of the Flow Stress of a Two- phase Alloy System Ti-6Al-4V[J]. Metall. Mater. Trans. A, 1996, 27(12): 3 957-3 962.

[3] Majorell A, Srivatsa S, Picu R C. Mechanical Behavior of Ti-6Al-4V at High and Moderate Temperatures-Part I: Experimental Results[J]. Mat. Sci. Eng. A, 2002, 326(2): 297-305.

[4] Zong Y Y, Shan D B, Xu M, et al. Flow Softening and Microstructural Evolution of TC11 Titanium Alloy during Hot Deformation[J]. J. Mater. Process. Tech., 2009, 209(4): 1 988-1 994.

[5] Mceldowney D J, Tamirisakandala S, Miracle D B. Heat-treatment Effects on the Microstructure and Tensile Properties of Powder Metallurgy Ti-6Al-4V Alloys Modified with Boron[J]. Metall. Mater. Trans. A, 2010, 41(4): 1 003-1 015.

[6] Zhang X Y, Li M Q, Li H, et al. Deformation Behavior in Isothermal Compression of the TC11 Titanium Alloy[J]. Mater. Des., 2010, 31(6): 2 851-2 857.

[7] Sun Q J, Wang G C, Li M Q. The Super Plasticity and Microstructure Evolution of TC11 Titanium Alloy[J]. Mater. Des., 2011, 32(7): 3 893-3 899.

[8] Littlewood P D, Wilkinson A J. Local Deformation Patterns in Ti-6Al-4V under Tensile, Fatigue and Dwell Fatigue Loading[J]. Int. J. Fatigue, 2012, 43: 111-119.

[9] Gu Y, Zeng F H, Qi Y L, et al. Tensile Creep Behavior of Heat-treated TC11 Titanium Alloy at 450–550 °C[J]. Mater Sci. Eng. A, 2013, 575: 74-85.

[10] Park C H, Kim J H, Hyun Y T, et al. The Origins of Flow Softening during High-temperature Deformation of a Ti-6Al-4V Alloy with a Lamellar Microstructure[J]. J. Alloys Compd., 2014, 582: 126-129.

[11] Follansbee P S, Gray G T. An Analysis of the Low Temperature, Low and High Strain-rate Deformation of Ti-6Al-4V[J]. Metall. Trans. A, 1989, 20(5): 863-874.

[12] Silva M G, Ramesh K T. The Rate-dependent Deformation and Localization of Fully Dense and Porous Ti-6Al-4V[J]. Mater. Sci. Eng. A, 1997, 232(1–2): 11-22.

[13] Lee W S, Lin C F. Plastic Deformation and Fracture Behavior of Ti-6Al-4V Alloy Loaded with High Strain Rate under Various Temperatures[J]. Mater. Sci. Eng. A, 1998, 241(1–2): 48-59.

[14] Chichili D R, Ramesh K T, Hemker K J. The High-strain-rate Response of Alpha-titanium: Experiments, Deformation Mechanisms and Modeling[J]. Acta Mater, 1998, 46(3): 1 025-1 043.

[15] Nemat-Nasser S, Guo W G, Nesterenko V F, et al. Dynamic Response of Conventional and Hot Isostatically Pressed Ti-6Al-4V Alloys: Experiments and Modeling[J]. Mech. Mater, 2001, 33(8): 425-439.

[16] Lee D G, Lee S, Lee C S, et al. Effects of Micro Structural Factors on Quasi-static and Dynamic Deformation Behaviors of Ti-6Al-4V Alloys with Widmanstätten Structures[J]. Metall. Mater Trans. A, 2003, 34(11): 2 541-2 548.

[17] Khan A, Kazmi R, Farrokh B, et al. Effect of Oxygen Content and Micro-structure on the Thermo-mechanical Response of Three Ti-6Al-4V Alloys: Experiments and Modeling over a Wide Range of Strain-rates and Temperatures[J]. Int. J. Plasticity, 2007, 23(7): 1 105-1 125.

[18] Luntz R D, Griffin R M, Green S J, et al. High-strain-rate Tests on Titanium 6-6-2 Utilizing a Unique Rate-testing Machine[J]. Exp. Mech., 1975, 15(10): 396-402.

[19] Fundenberger J J, Philippe M J, Wagner F, et al. Modeling and Prediction of Mechanical Properties for Materials with Hexagonal Symmetry (Zinc, Titanium and Zirconium Alloys)[J]. Acta Mater, 1997, 45: 4 041-4 055.

[20] Gall K, Sehitoglu H, Chumlyakov Y I, et al. Tension-compression Asymmetry of the Stress-strain Response in Aged Single Crystal and Polycrystalline NiTi[J]. Acta. Mater, 1999, 47(4): 1 203-1 217.

[21] Williams J C, Baggerly R G, Paton N E. Deformation Behavior of HCP Ti-Al Single Crystals[J]. Metall. Mater Trans. A, 2002, 33(13): 837-850.

[22] Cheng S, Spencer J A, Milligan W W. Strength and Tension/compression Asymmetry in Nanostructured and Ultra Fine-grain Metals[J]. Acta Mater, 2003, 51(15): 4 505-4 518.

[23] Macdougall D A S, Harding J. A Constitutive Relation and Failure Criterion for Ti-6Al-4V Alloy at Impact Rates of Strain[J]. J. Mech. Phys. Solids, 1999, 47(5): 1 157-1 185.

[24] Roy S, Suwas S. The Influence of Temperature and Strain Rate on the Deformation Response and Microstructural Evolution during Hot Compression of a Titanium Alloy Ti-6Al-4V-0.1B[J]. J. Alloys Compd., 2013, 548(4): 110-125.

[25] Kotkunde N, Deole A D, Gupta A K, et al. Comparative Study of Constitutive Modeling for Ti-6Al-4V Alloy at Low Strain Rates and Elevated Temperatures[J]. Mater Des., 2014, 55: 999-1005.

[26] Huang W, Zan X, Nie X, et al. Experimental Study on the Dynamic Tensile Behavior of a Poly-crystal Pure Titanium at Elevated Temperatures[J]. Mat. Sci. Eng. A, 2007, 443(1–2): 33-41.

[27] Kapoor R, Nemat-Nasser S. Determination of Temperature Rise during High Strain Rate Deformation[J]. Mech. Mater, 1998, 27(1): 1-12.