Superplasticity in the Ti–6Al–7Nb alloy processed by high-pressure torsion

Ashida, Maki; Chen, Peng; Doi, Hisashi; Tsutsumi, Yusuke; Hanawa, Takao; Horita, Zenji

doi:10.1016/j.msea.2015.06.020

Cited by 39 publications

(20 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The advent of superplastic elongation on the same material is consistent with a recent report after processing by HPT. [41] A TEM micrograph of the HPS-processed sample is shown in Figure 10 with a bright-field image on the left and dark-field image on the right including an SEAD pattern at the center. The arrow in the SAED pattern indicates a diffracted beam for the dark-field imaging.…”

Section: Methodsmentioning

confidence: 99%

Scaling up of High-Pressure Sliding (HPS) for Grain Refinement and Superplasticity

Takizawa

Masuda

Fujimitsu

et al. 2016

Metall Mater Trans A

Self Cite

View full text Add to dashboard Cite

The process of high-pressure sliding (HPS) is a method of severe plastic deformation developed recently for grain refinement of metallic materials under high pressure. The sample for HPS is used with a form of sheet or rod. In this study, an HPS facility with capacities of 500 tonnes for vertical pressing and of 500 and 300 tonnes for horizontal forward and backward pressings, respectively, was newly built and applied for grain refinement of a Mg alloy as AZ61, Al alloys such as Al-Mg-Sc, A2024 and A7075 alloys, a Ti alloy as ASTM-F1295, and a Ni-based superalloy as Inconel 718. Sheet samples with dimensions of 10 to 30 mm width, 100 mm length, and 1 mm thickness were processed at room temperature and ultrafine grains with sizes of~200 to 300 nm were successfully produced in the alloys. Tensile testing at elevated temperatures confirmed the advent of superplasticity with total elongations of more than 400 pct in all the alloys. It is demonstrated that the HPS can make all the alloys superplastic through processing at room temperature with a form of rectangular sheets.

show abstract

Section: Methodsmentioning

confidence: 99%

Scaling up of High-Pressure Sliding (HPS) for Grain Refinement and Superplasticity

Takizawa

Masuda

Fujimitsu

et al. 2016

Metall Mater Trans A

Self Cite

View full text Add to dashboard Cite

show abstract

“…This phenomenon could be explained by the re nement of grain size of the alloys. We have previously shown that after HPT processing grain size of the α phase decreased from 5 µm in HPT-0 to about 100 nm or 70 nm in HPT-2 and HPT-6, respectively 1) , which could result in enhanced surface oxidation. In general, no signi cant change in surface chemical composition of specimens was observed by XPS.…”

Section: Surface Chemical Compositionmentioning

confidence: 97%

“…The specimens with and without HPT processing were prepared as described previously 1) . Brie y, a Ti-6Al-7Nb alloy rod with a diameter of 10 mm was prepared and cut into 0.8-mmthick slices.…”

Section: Specimen Preparationmentioning

confidence: 99%

“…However, as an α+β type Ti alloy, it has limited cold-formability due to high strength and low ductility. In a previous work 1) , we successfully employed high-pressure torsion (HPT) processing to improve the mechanical properties of the Ti-6Al-7Nb alloy. HPT increased tensile strength while maintaining the elongation.…”

Section: Introductionmentioning

confidence: 99%

“…HPT increased tensile strength while maintaining the elongation. This was attained by decreasing grain size of the alloy from 5 µm to about 100 nm 1) . However, the cytocompatibility of this HPT processed Ti alloy has not been assessed yet.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Cytocompatibility of Ti–6Al–7Nb through High-Pressure Torsion Processing

et al. 2016

Self Cite

View full text Add to dashboard Cite

In this study, we evaluated the cytocompatibility of high-pressure torsion (HPT)-processed Ti-6Al-7Nb alloys. Grain size of titanium (Ti) alloys decreased from 5 µm (without HPT processing, HPT-0) to 100 nm (at 2 GPa, HPT-2) or 70 nm (at 6 GPa, HPT-6) through HPT processing. Cell adhesion, proliferation, and differentiation were evaluated with mouse preosteoblast (MC3T3-E1). A locomotion trend was presented by cells cultured on HPT-2 to compare with other specimens, while, an immobilization trend was presented by cells cultured on HPT-6 to compare with other specimens. Akp2 (alkaline phosphatase 2) expression was higher in cells cultured on HPT-2 than that on HPT-0 and HPT-6, indicating enhanced osteogenic differentiation. Our results demonstrate that HPT-processed Ti-6Al-7Nb alloys offer good cytocompatibility.

show abstract