Microstructure and tensile strength of grade 2 titanium processed by equal-channel angular pressing and by rolling

Sordi, Vitor Luiz; Ferrante, M.; Kawasaki, Megumi; Langdon, Terence G.

doi:10.1007/s10853-012-6593-x

Cited by 69 publications

(56 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The H-P relationship for Ti; [81] grades 1 to 4 denote increasing orders of impurities for Fe, N and O and using experimental data. [81][82][83][84][85][86][87][88][89][90][91][92][93][94][95][96][97][98][99][100] Figure 4. The H-P relationship for coarse-grained and HPT processed Al-5% Mg; [103] with increasing numbers of turns, HAGBs develop and the H-P relationship is followed so that data from coarse grain samples fall on the same line as HPT specimens.…”

Section: Figure Captionsmentioning

confidence: 99%

The Strength–Grain Size Relationship in Ultrafine-Grained Metals

Balasubramanian

Langdon

2016

Metall Mater Trans A

Self Cite

View full text Add to dashboard Cite

Metals processed by severe plastic deformation [SPD] techniques, such as equal-channel angular pressing [ECAP] and high-pressure torsion [HPT], generally have submicrometer grain sizes. Consequently, they exhibit high strength as expected on the basis of the HallPetch [H-P] relationship. Examples of this behavior are discussed using data on Ti, Al-Mg 1 and Ni. These materials typically have grain size above ~50 nm where softening is not expected. An increase in strength is usually accompanied by a decrease in ductility. High strength and ductility can be achieved simultaneously by imposing high strains to give both ultrafine grain sizes and a high fraction of high-angle grain boundaries. An example is presented for a cast Al-7% Si alloy processed by HPT. In some cases, SPD may produce a fine grain size but also lead to a weakening due to microstructural changes as in ECAP of an Al-7034 alloy and HPT of Zn-22% Al. In SPD-processed materials, grain boundary segregation and nanostructural features are present which may lead to higher strengths than those predicted by the H-P relationship in some alloys having nano grain sizes.

show abstract

Section: Figure Captionsmentioning

confidence: 99%

The Strength–Grain Size Relationship in Ultrafine-Grained Metals

Balasubramanian

Langdon

2016

Metall Mater Trans A

Self Cite

View full text Add to dashboard Cite

show abstract

“…4 illustrates the true stress-true strain curves of CP-Ti under dynamic compression at strain rates of ~3000 and ~4500 s -1 over a range of temperatures. It is readily apparent that the flow stress behavior is strongly influenced by the testing temperature so that, with an increase in temperature from 298 to 673 K, the flow stress decreases and the fracture strain 8 increases at both strain rates.…”

Section: Microstructures After Dynamic Compressionmentioning

confidence: 99%

“…Nevertheless, the low strength of pure Ti tends to significantly reduce the potential applications. Through the introduction of severe plastic deformation (SPD) techniques, and combinations of SPD with other traditional deformation procedures, it is possible to fabricate ultrafine-grained (UFG) and nanocrystalline (NC) Ti which shows excellent properties including enhanced strength and good ductility [3][4][5][6][7][8][9].…”

Section: Introductionmentioning

confidence: 99%

“…Equal-channel angular pressing (ECAP) [10], one of the major SPD techniques, is especially attractive for fabricating relatively large volumes of homogeneously deformed bulk UFG/NC materials [11][12][13][14][15] and some reports suggest that a two-step processing route of ECAP combined with drawing [16][17][18], extrusion [19,20] or rolling [8,21] may be utilized successfully to even further improve the mechanical properties of UFG/NC Ti.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Temperature and strain rate dependence of microstructural evolution and dynamic mechanical behavior in nanocrystalline Ti

Zhang

Wang

Zhilyaev

et al. 2015

Materials Science and Engineering: A

Self Cite

View full text Add to dashboard Cite

The mechanical behavior of commercial purity titanium with a nanocrystalline (NC) grain size was investigated using split Hopkinson pressure bar tests at high strain rates and over a range of temperatures. The study was accompanied by detailed microstructural investigations before and after compression testing. The results show that rotary dynamic recrystallization operates during compressive deformation at strain rates of ~3000 and ~4500 s -1 at temperatures from 298 to 573 K but cells form at 673 K. The dynamic mechanical behavior of NC Ti shows a strong dependence on temperature and strain rate such that the flow stress and the strain hardening rate both increase with increasing strain and decreasing temperature. A constitutive equation is derived to relate the flow stress to the temperature, strain rate and true strain and to predict the yield strength and the peak stress of NC Ti subjected to dynamic deformation at elevated temperatures.

show abstract

“…The activation of twinning in CP-Ti is affected by many factors, such as deformation temperature, strain rate, deformation value, deformation direction [20,21]. Prior deformation (cold rolling and ECAP) produces many twins in the initial microstructure of CP-Ti, which is different from tensile prestrain [18,19,[22][23][24]. The effects of stretching prestrain on the mechanical properties of CP-Ti have not been examined.…”

Section: Introductionmentioning

confidence: 99%

The Effects of Prestrain and Subsequent Annealing on Tensile Properties of CP-Ti

Chang

Zhou

2017

Metals

View full text Add to dashboard Cite

Abstract:The aim of the present work is to investigate the effects of prestrain and subsequent annealing on tensile properties of commercial pure titanium (CP-Ti). According to tensile test results, yield strength and ultimate tensile strength increase with the increase of prestrain. Elongation and uniform strain decrease linearly with prestrain. In the case of prestrain that is higher than 3.5%, the macro-yield of specimens changes from gradual yielding to discontinuous yielding. It is supposed that considerable numbers of dislocations introduced into the material lead to the appearance of yield plateau. The quantitative analysis of the contribution of dislocation hardening to the strain hardening shows that dislocation-associated mechanisms play an important role in strain hardening. Moreover, a modified Fields-Backofen model is proposed to predict the flow stress of prestrained CP-Ti at different strain rates. Both strain rate sensitivity and strain hardening exponent decrease with prestrain. Fracture surfaces of the specimens show that fracture mechanism of all tested specimens is dimple fracture. The more ductile deformation in prestrained CP-Ti after annealing indicates that its ductility is improved by annealing.

show abstract

Microstructure and tensile strength of grade 2 titanium processed by equal-channel angular pressing and by rolling

Cited by 69 publications

References 23 publications

The Strength–Grain Size Relationship in Ultrafine-Grained Metals

The Strength–Grain Size Relationship in Ultrafine-Grained Metals

Temperature and strain rate dependence of microstructural evolution and dynamic mechanical behavior in nanocrystalline Ti

The Effects of Prestrain and Subsequent Annealing on Tensile Properties of CP-Ti

Contact Info

Product

Resources

About