Submicrosecond strength of ultrafine-grained materials

Garkushin, G. V.; Ignatova, O. N.; Kanel, G. I.; Meyer, Lothar; Разоренов, С. В.

doi:10.3103/s0025654410040114

Cited by 30 publications

(12 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…observed for other metals [7]. The maximum com pressive strain rate in the shock wave = /2U S in accordance with the measured values of the maximum acceleration of the free surface , which are equal to 26 (km/s) μs -1 for coarse grained tantalum and 47 (km/s) μs -1 for ultrafine grained tan talum at a plastic shock wave velocity of 3.7 km/s, is estimated to be 3.5 × 10 6 s -1 for coarse grained tanta lum and 6.4 × 10 6 s -1 for ultrafine grained tantalum.…”

Section: Flow Stress Of Tantalummentioning

confidence: 73%

“…However, the data available in the literature on the influence of these factors on the flow stress and strength of materials under high strain rate loading [5][6][7][8] are very scarce and contradictory. While the hard ness, yield stress, and tensile strength, which are mea sured under low strain rate loading, increase after severe plastic deformation or shock wave loading of the material, changes in the resistance to high strain rate loading and fracture can be not observed or even have the opposite sign.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Resistance to dynamic deformation and fracture of tantalum with different grain and defect structures

et al. 2012

Self Cite

View full text Add to dashboard Cite

This paper presents the results of measurements of the strength properties of technically pure tan talum under shock wave loading. It has been found that a decrease in the grain size under severe plastic defor mation leads to an increase in the hardness of the material by approximately 25%, but the experimentally measured values of the dynamic yield stress for the fine grained material prove to be less than those of the ini tial coarse grained specimens. This effect has been explained by a higher rate of stress relaxation in the fine grained material. The hardening of tantalum under shock wave loading at a pressure in the range 40-100 GPa leads to a further increase in the rate of stress relaxation, a decrease in the dynamic yield stress, and the dis appearance of the difference between its values for the coarse grained and fine grained materials. The spall strength of tantalum increases by approximately 5% with a decrease in the grain size and remains unchanged after the shock wave loading. The maximum fracture stresses are observed in tantalum single crystals.

show abstract

Section: Flow Stress Of Tantalummentioning

confidence: 73%

Section: Introductionmentioning

confidence: 99%

Resistance to dynamic deformation and fracture of tantalum with different grain and defect structures

et al. 2012

Self Cite

View full text Add to dashboard Cite

show abstract

“…Hardening of a material by decreasing grain size or by other method may appear or not appear in increase of the HEL value depending on the branch of the ) ( p γ τ dependence which is realized for chosen sample thickness [20]. Moreover, it was observed [21] that harder ultra-fine-grained tantalum may demonstrate even lower HEL value than less hard coarse-grained one.…”

Section: Precursor Decay and Initial Plastic Strain Ratementioning

confidence: 94%

Rate and temperature effects on the flow stress and tensile strength of metals

Kanel

2012

AIP Conference Proceedings

View full text Add to dashboard Cite

Some new and obtained earlier experimental data on the elastic precursor decay and rise times of plastic shock waves in several metals and alloys at normal and elevated temperatures are discussed. The time range available for measurements has been expanded to picoseconds that allows approaching ultimate shear and tensile strengths and observations of general trends. Results of measurements have been transformed into dependences of plastic strain rate on the shear stress.

show abstract

“…On the other hand, the data on the influence of these factors on flow stresses and material strength under high strain rates is very sparse and often contradictory [3,4].…”

Section: Introductionmentioning

confidence: 99%

“…Tantalum has a high density (16.65 g/cm 3 ), melting temperature (2996 0 C) and is unique in it's combination of high hardness with high plasticity. Extensive research and publications are dedicated to investigations of the elastic-plastic properties and spall fracture of tantalum under shock-wave loading [5][6][7][8][9], but the question about the influence of structural factors on these processes remains unanswered.…”

Section: Introductionmentioning

confidence: 99%

The spall strength and Hugoniot elastic limit of tantalum with various grain size

Разоренов

Garkushin

Kanel

et al. 2012

AIP Conference Proceedings

View full text Add to dashboard Cite

Abstract. The VISAR free surface velocity histories have been measured for commercial grade coarse grain (CG, 50 -60 μm) and ultra fine grained (UFG, ~0.5 μm grain size) after severe plastic deformation tantalum and for comparison tantalum single crystals, at peak stresses around 12-14 GPa and strain rates of 10 5 -10 6 s -1 . The decrease in the grain size, which resulted in ~25 % increase of the hardness did not cause any significant influence on the HEL, the value of which is ~2 GPa, but increases slightly the spall strength of the UFG tantalum (7.4 GPa) in comparison with the CG samples (~7 GPa). In both cases the spall strength does not noticeably vary with increase of the peak shock stress up to 70 GPa. The experiments using samples precompressed at 40 and 100 GPa peak pressure have confirmed weak influence of preceding shock compression on the tantalum spall strength. The tantalum single crystals display the highest spall strength equal to ~10 GPa. The influences of the grain size on static and dynamic yield stresses are discussed in terms of general strain rate effects.

show abstract

Submicrosecond strength of ultrafine-grained materials

Cited by 30 publications

References 9 publications

Resistance to dynamic deformation and fracture of tantalum with different grain and defect structures

Resistance to dynamic deformation and fracture of tantalum with different grain and defect structures

Rate and temperature effects on the flow stress and tensile strength of metals

The spall strength and Hugoniot elastic limit of tantalum with various grain size

Contact Info

Product

Resources

About