A study of deformation twinning in a titanium alloy by X-ray diffraction contrast tomography

Nervo, Laura; King, Andrew; Fitzner, Arnas; Ludwig, Wolfgang; Preuss, Michael

doi:10.1016/j.actamat.2015.12.032

Cited by 60 publications

(33 citation statements)

References 79 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The optimum slip system parameters of Ti-0Al are shown in Table 1. The only information in literature [26], to the best of the author's knowledge, discusses that the s 0 value of the pyramidal < c + a > slip system should be three to five times higher than the s 0 value of the prismatic < a > slip system. This statement in Reference [26] is supported by the optimization results reported in Table 1.…”

Section: Optimization Of Slip System Parameters For Ti-0almentioning

confidence: 99%

“…The only information in literature [26], to the best of the author's knowledge, discusses that the s 0 value of the pyramidal < c + a > slip system should be three to five times higher than the s 0 value of the prismatic < a > slip system. This statement in Reference [26] is supported by the optimization results reported in Table 1. The true stress -true strain curves, which are predicted using the optimum slip system parameters of the ODF based crystal plasticity model, are compared to the experimental data in Figure 1 for tension and compression respectively.…”

Section: Optimization Of Slip System Parameters For Ti-0almentioning

confidence: 99%

“…They found the compression twins to be very difficult to nucleate in Ti-Al single crystals when the Al content is more than 5 wt %. Khan et al [31] discussed that the Ti-Al alloy with 6 wt % Al does not twin even at temperatures as low as 100 K. On the other hand, some references [26,32,33] claim that Al addition has an increasing effect up to a peak level and then after this point the further Al addition suppresses the twinning effect. Fitzner et al [33] performed a detailed experimental study to investigate the effect of Al addition to twinning activity in Ti-Al alloys, and they found that at around 7 at % Al there is a turning point in twinning activity and a further increase in Al reduced the twinning activity because of short range ordering and signs of Ti 3 Al formation in case of the highest Al content they observed (13 at %).…”

Section: Introductionmentioning

confidence: 99%

“…In addition, twinning is commonly observed in Ti and other metals with an HCP crystal structure, and it has a strong effect on the overall behavior of a polycrystal material [27]. The deformation behavior of HCP-Ti and Ti alloys has been studied in literature extensively [26][27][28][29][30][31][32][33]. These studies revealed that the Ti alloys have complex slip and twinning modes.…”

Section: Introductionmentioning

confidence: 99%

“…The number of the slip systems determines the design variables here since the optimization is performed for the parameters of all active slip systems. Metals having a hexagonal close-packed (HCP) crystal structure, such as titanium (Ti), are expected to display easy < a > slip, either on the prismatic or basal plane [26]. The observed slip systems in pure HCP titanium (HCP-Ti) are the three equivalent basal 0001 < 1120 >, three equivalent prismatic 1010 < 1120 > and six equivalent pyramidal 1011 < 1120 > slip systems [27].…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Crystal Plasticity Modeling and Experimental Validation with an Orientation Distribution Function for Ti-7Al Alloy

Acar

Ramazani

Sundararaghavan

2017

Metals

View full text Add to dashboard Cite

An orientation distribution function based model is used for micromechanical modeling of the titanium-aluminum alloys, Ti-0 wt % Al and Ti-7 wt % Al, which are in demand for many aerospace applications. This probability descriptor based modeling approach is different than crystal plasticity finite element techniques since it computes the averaged material properties using upper bound averaging. A rate-independent single-crystal plasticity model is implemented to compute the effect of macroscopic strain on the polycrystal. An optimization problem is defined for calibrating the basal, prismatic, pyramidal slip system and twin parameters using the available tension and compression experimental data. The crystal plasticity parameters of Ti-7 wt % Al are not studied extensively in literature, and therefore the optimization results for the crystal plasticity model realization produce unique data, which will be beneficial to future studies in the field. The sensitivities of the slip and twin parameters to the design objectives are also investigated to identify the most critical slip system parameters. Using the optimum design parameters, the microstructural textures, during the tension test, are predicted by the crystal plasticity finite element simulations, and compared to the available experimental texture and scanning electron microscope-digital image correlation data.

show abstract

Section: Optimization Of Slip System Parameters For Ti-0almentioning

confidence: 99%

Section: Optimization Of Slip System Parameters For Ti-0almentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Crystal Plasticity Modeling and Experimental Validation with an Orientation Distribution Function for Ti-7Al Alloy

Acar

Ramazani

Sundararaghavan

2017

Metals

View full text Add to dashboard Cite

show abstract

Verfügbare Analytikmethoden und ‐geräte

2023

Charakterisierung Von Holz‐ Und Naturfasern

View full text Add to dashboard Cite

Ultralow Temperature Densification of a Titanium Alloy by Spark Plasma Sintering

et al. 2020

View full text Add to dashboard Cite

Full densification of a Ti alloy (Ti6Al4V) is achieved at unprecedented low temperatures of 650 °C and 555 MPa by spark plasma sintering (SPS) without any sintering aid. The alloy demonstrates a globular equiaxed microstructure with comparable mechanical properties as that sintered at conventional high temperatures (950 °C, 60 MPa). In contrast with the diffusion‐driven sintering of the Ti alloy at conventional SPS conditions, the near‐full densification (99%) attained at low‐temperature/high‐pressure regimes is attributed to plastic deformation‐driven mass transport processes. Sintering pressures of 555 MPa result in a dislocation dense microstructure and the activation of compressive twins imparting lattice strains of up to 2.86 × 10−3, suggesting a 25% increase in lattice distortions as compared with those sintered at moderate pressures of 60 MPa. Depth‐sensing nanoscale indentation reveals the globular microstructure of the high‐pressure‐sintered alloy to retain its elastic modulus and hardness of 138 and 4.8 GPa, respectively, with <2% deviation from those sintered at conventional SPS temperatures. This energy‐efficient technique proposes an alternative to thermally exhaustive routines and presents an advantage for engineering titanium‐matrix composites with nanofillers and controlled reaction products by reducing processing temperatures by up to 300 °C.

show abstract

A study of deformation twinning in a titanium alloy by X-ray diffraction contrast tomography

Cited by 60 publications

References 79 publications

Crystal Plasticity Modeling and Experimental Validation with an Orientation Distribution Function for Ti-7Al Alloy

Crystal Plasticity Modeling and Experimental Validation with an Orientation Distribution Function for Ti-7Al Alloy

Verfügbare Analytikmethoden und ‐geräte

Ultralow Temperature Densification of a Titanium Alloy by Spark Plasma Sintering

Contact Info

Product

Resources

About