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Research Papers

Dynamic Mechanical Behavior of Additively Manufactured Ti6Al4V With Controlled Voids

[+] Author and Article Information
Refael Fadida

Rafael,
POB 2250,
Haifa 3102102, Israel
e-mail: fadidarafi@gmail.com

Daniel Rittel

Faculty of Mechanical Engineering,
Technion, Haifa 3200003, Israel
e-mail: rittel@me.technion.ac.il

Amnon Shirizly

Rafael,
POB 2250,
Haifa 3102102, Israel
e-mail: a.shirizly@gmail.com

1Corresponding author.

Contributed by the Applied Mechanics Division of ASME for publication in the JOURNAL OF APPLIED MECHANICS. Manuscript received November 25, 2014; final manuscript received February 4, 2015; published online February 26, 2015. Assoc. Editor: Weinong Chen.

J. Appl. Mech 82(4), 041004 (Apr 01, 2015) (9 pages) Paper No: JAM-14-1539; doi: 10.1115/1.4029745 History: Received November 25, 2014; Revised February 04, 2015; Online February 26, 2015

The mechanical properties of additively manufactured (AM) dense and porous Ti6Al4V specimens were investigated under static and dynamic compression. The fully dense specimens were fabricated using laser melting process. The porous specimens contained spherical pores with full control on the geometry and location of the pores. The laser processed dense material exhibited superior strength in the static and dynamic tests, compared to the same conventional material, but the ductility of the two was comparable. Single pore specimens exhibited a linear relationship between the load and the pore volume fraction. The comparison between single- and double-pore specimens, at identical volume fractions, revealed the importance of the pores' orientation with respect to the applied load.

Copyright © 2015 by ASME
Topics: Compression , Failure , Stress
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References

Veiga, C., Davim, J. P., and Loureiro, A. J. R., 2012, “Properties and Applications of Titanium Alloys: A Brief Review,” Rev. Adv. Mater. Sci., 32(2), pp. 133–148 http://www.ipme.ru/e-journals/RAMS/no_23212/05_23212_veiga.pdf.
Nicholas, T., 1980, “Dynamic Tensile Testing of Structural Materials Using a Split Hopkinson Bar Apparatus,” Air Force Wright Aeronautical Laboratories (AFSC), Wright-Patterson Air Force Base, OH, Report No. AFWAL-TR-80-4053.
Wulf, G. L., 1979, “High Strain Rate Compression of Titanium and Some Titanium Alloys,” Int. J. Mech. Sci., 21(12), pp. 713–718. [CrossRef]
ASTM, 2014, “Standard Specification for Additive Manufacturing Titanium-6 Aluminum-4 Vanadium With Powder Bed Fusion,” ASTM International, West Conshohocken, PA, Standard No. F2924-14, available at: http://www.astm.org/Standards/F2924.htm
Gu, D. D., 2012, “Laser Additive Manufacturing of Metallic Components: Materials, Processes and Mechanisms,” Int. Mater. Rev., 57(3), pp. 133–164. [CrossRef]
Kruth, J.-P., 2005, “Binding Mechanisms in Selective Laser Sintering and Selective Laser Melting,” Rapid Prototyping J., 11(1), pp. 26–36. [CrossRef]
Benzerga, A. A., and Leblond, J., 2010, “Ductile Fracture by Void Growth to Coalescence,” Adv. Appl. Mech., 44, pp. 169–305. [CrossRef]
Gurson, A. L., 1977, “Continuum Theory of Ductile Rupture by Void Nucleation and Growth: Part I—Yield Criteria and Flow Rules for Porous Ductile Media,” ASME J. Eng. Mater. Technol., 99(1), pp. 2–15 [CrossRef].
Tvergaard, V., 1982, “On Localization in Ductile Materials Containing Spherical Voids,” Int. J. Fract., 18(4), pp. 237–252 [CrossRef].
Nahshon, K., and Hutchinson, J. W., 2008, “Modification of the Gurson Model for Shear Failure,” Eur. J. Mech. A. Solids, 27(1), pp. 1–17. [CrossRef]
Xue, Z., Faleskog, J., and Hutchinson, J. W., 2013, “Tension–Torsion Fracture Experiments—Part II: Simulations With the Extended Gurson Model and a Ductile Fracture Criterion Based on Plastic Strain,” Int. J. Solids Struct., 50(25–26), pp. 4258–4269. [CrossRef]
da Silva, M. G., and Ramesh, K. T., 1997, “The Rate-Dependent Deformation and Localization of Fully Dense and Porous Ti-6Al-4V,” Mater. Sci. Eng., A, 232(1–2), pp. 11–22. [CrossRef]
Biswas, N., Ding, J. L., and Balla, V. K., 2012, “Deformation and Fracture Behavior of Laser Processed Dense and Porous Ti6Al4V Alloy Under Static and Dynamic Loading,” Mater. Sci. Eng., A, 549, pp. 213–221. [CrossRef]
Biswas, N., and Ding, J., 2014, “Numerical Study of the Deformation and Fracture Behavior of Porous Ti6Al4V Alloy Under Static and Dynamic Loading,” Int. J. Impact Eng. (in press) [CrossRef].
Kolsky, H., 1949, “An Investigation of the Mechanical Properties of Materials at Very High Rates of Loading,” Proc. Phys. Soc., London, Sect. B, 62(11), p. 676. [CrossRef]
Davies, E. D. H., 1963, “The Dynamic Compression Testing of Solids by the Method of the Split Hopkinson Pressure Bar,” J. Mech. Phys. Solids, 11(3) pp. 155–179. [CrossRef]
Ramesh, K. T., 2008, “High Rates and Impact Experiments,” Springer Handbook of Experimental Solid Mechanics, Springer, New York, pp. 929–960.
Sano, T., Kato, K., and Takeishi, H., 1995, “Analysis of Dynamic Deformation Mechanisms in Powder Metals,” J. Mater. Process. Technol., 48(1–4), pp. 391–397. [CrossRef]
Peirs, J., Tirry, W., and Amin-Ahmadi, B., 2012, “Microstructure of Adiabatic Shear Bands in Ti6Al4V,” Mater. Charact., 75, pp. 79–92 [CrossRef].
Osovski, S., Nahmany, Y., and Rittel, D., 2012, “On the Dynamic Character of Localized Failure,” Scr. Mater., 67(7–8), pp. 693–695. [CrossRef]
Leblond, J.-B., Perrin, G., and Devaux, J., 1995, “An Improved Gurson-Type Model for Hardenable Ductile Metals,” Eur. J. Mech. A. Solids, 14(4), pp. 499–527.
Mear, M. E., and Hutchinson, J. W., 1984, “Influence of Yield Surface Curvatura on Flow Localization in Dilatant Plasticity,” Mech. Mater., 4(3–4), pp. 395–407 [CrossRef].
Perrin, G., and Leblond, J. B., 1990, “Analytical Study of a Hollow Sphere Made of Plastic Porous Material and Subjected to Hydrostatic Tension-Application to Some Problems in Ductile Fracture of Metals,” Int. J. Plast., 6(6), pp. 677–699. [CrossRef]
Benzerga, A. A., Besson, J., and Pineau, A., 1999, “Coalescence-Controlled Anisotropic Ductile Fracture,” ASME J. Eng. Mater. Technol., 121(2), pp. 221–229. [CrossRef]

Figures

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Fig. 6

X-ray image of axial double pore specimen with varying d/B ratio

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Fig. 7

Typical force equilibrium of printed Ti6Al4V specimen, in dynamic compression. F-in and F-out stand for incident and transmitted force, respectively.

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Fig. 5

A set of single pore specimens in X-ray image

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Fig. 4

A cross section of a single pore specimen. (a) An example of residual powder inside a pore. (b) A Ø2 mm pore, after the powder removal. Note the relatively accurate geometry of the spherical pore.

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Fig. 3

Double pore specimen: axial, lateral, and diagonal, respectively, from left to right

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Fig. 2

Single pore specimen

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Fig. 1

(a) An example of a batch of specimens, (b) wire cutting of specimen, and (c) compression specimen

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Fig. 8

Fully dense printed Ti6Al4V compared to conventional material in quasi-static compression at nominal strain rate of 1 × 10−3 s−1

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Fig. 9

Failure of printed Ti6Al4V specimen in quasi-static compression. Note the shear failure pattern.

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Fig. 10

Fully dense printed Ti6Al4V in dynamic compression compared to conventional material at nominal strain rate of 2 × 103s−1

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Fig. 11

Typical dynamic fracture of fully dense printed Ti6Al4V specimen. Note the shear fracture pattern.

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Fig. 12

SEM image of printed Ti6Al4V failure. Note the elongated dimples.

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Fig. 13

Typical true stress–strain curve of printed Ti6Al4V at different strain rates. Note that once in the dynamic regime, the influence of the strain rate becomes minor. Note also the lack of strain hardening in the high rate regime.

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Fig. 14

Force as a function of displacement for different pore size. Note the decrease in load and displacement to failure as the pore diameter increases.

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Fig. 15

Force as a function of volume fraction for a single pore specimen. The displacement is arbitrarily fixed to 0.4 mm.

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Fig. 21

Dynamic compression of single pore compared to double pore with 1.6% volume fraction at 0.4 mm elongation

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Fig. 22

SEM image of a diagonal double pore specimen failure. Note the remained powder, which can be related to the rapid failure.

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Fig. 16

Failure of a single pore specimen. (a) Pore Ø1 mm and (b) pore Ø2 mm.

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Fig. 17

SEM image of a single pore specimen failure at Ø2 mm pore size

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Fig. 18

SEM image of a single pore specimen failure

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Fig. 19

Dynamic compression of double pored specimen in all orientations. (a) d/B = 1, (b) d/B = 2, and (c) d/B = 4.

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Fig. 20

Dynamic compression of double pore specimen in all d/B ratios. (a) Axial, (b) lateral, and (c) diagonal.

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