M. F. Ashby and R. A. Verrall, Diffusion-accommodated flow and superplasticity, Acta Metallurgica, vol.21, issue.2, pp.149-163, 1973.
DOI : 10.1016/0001-6160(73)90057-6

D. H. Bae and A. K. Ghosh, Grain size and temperature dependence of superplastic deformation in an Al???Mg alloy under isostructural condition, Acta Materialia, vol.48, issue.6, pp.1207-1224, 2000.
DOI : 10.1016/S1359-6454(99)00445-0

A. Belyakov, T. Sakai, H. Miura, and K. Tsuzaki, Grain refinement in copper under large strain deformation, Philosophical Magazine A, vol.6, issue.11, pp.2629-2643, 2001.
DOI : 10.1016/S1359-6454(96)00156-5

T. H. Blewitt, R. R. Coltman, and J. K. Redman, Low???Temperature Deformation of Copper Single Crystals, Journal of Applied Physics, vol.28, issue.6
DOI : 10.1063/1.1722824

B. Cai, Q. P. Kong, L. Lu, and K. Lu, Interface controlled diffusional creep of nanocrystalline pure copper, Scripta Materialia, vol.41, issue.7, pp.755-759, 1999.
DOI : 10.1016/S1359-6462(99)00213-4

Y. Champion and J. Bigot, Characterization of nanocrystalline copper powders prepared by melting in a cryogenic liquid, Materials Science and Engineering: A, vol.217, issue.218, pp.58-63, 1996.
DOI : 10.1016/S0921-5093(96)10291-4

Y. Champion, C. Langlois, S. Guérin-mailly, P. Langlois, J. Bonnentien et al., Near-Perfect Elastoplasticity in Pure Nanocrystalline Copper, Science, vol.300, issue.5617, pp.310-311, 2003.
DOI : 10.1126/science.1081042

Y. Champion, F. Bernard, N. Guigue-millot, and P. Perriat, Sintering of copper nanopowders under hydrogen: an in situ X-ray diffraction analysis, Materials Science and Engineering: A, vol.360, issue.1-2, pp.258-263, 2003.
DOI : 10.1016/S0921-5093(03)00446-5

URL : https://hal.archives-ouvertes.fr/hal-00475132

Y. Champion, J. Bonnentien, C. Langlois, C. Duhamel, J. Moulin et al., Synthesis and Processing of Metallic Nano-Powders for the Study of their Mechanical and Magnetic Properties, Materials Science Forum, vol.426, issue.432, pp.426-4322411, 2003.
DOI : 10.4028/www.scientific.net/MSF.426-432.2411

Y. Champion and J. Bigot, Synthesis and structural analysis of aluminum nanocrystalline powders, Nanostructured Materials, vol.10, issue.7, pp.1097-1110, 1998.
DOI : 10.1016/S0965-9773(98)00149-4

M. Chen, E. Ma, K. J. Hemker, H. Sheng, Y. Wang et al., Deformation Twinning in Nanocrystalline Aluminum, Science, vol.300, issue.5623, pp.1275-1277, 2003.
DOI : 10.1126/science.1083727

S. Cheng, J. A. Spencer, and W. W. Milligan, Strength and tension/compression asymmetry in nanostructured and ultrafine-grain metals, Acta Materialia, vol.51, issue.15, pp.4505-4518, 2003.
DOI : 10.1016/S1359-6454(03)00286-6

A. H. Chokshi, A. Rosen, J. Karch, and H. Gleiter, On the validity of the hall-petch relationship in nanocrystalline materials, Scripta Metallurgica, vol.23, issue.10, pp.1679-1684, 1989.
DOI : 10.1016/0036-9748(89)90342-6

A. H. Cottrell, Dislocations and Plastic Flow in Crystals, American Journal of Physics, vol.22, issue.4, 1953.
DOI : 10.1119/1.1933704

M. F. Doerner and W. D. Nix, A method for interpreting the data from depth-sensing indentation instruments, Journal of Materials Research, vol.36, issue.04, pp.601-609, 1986.
DOI : 10.1016/0020-7225(65)90019-4

O. Domingez, Y. Champion, and J. Bigot, Liquidlike sintering behavior of nanometric Fe and Cu powders: Experimental approach, Metallurgical and Materials Transactions A, vol.204, issue.69, pp.2941-2949, 1998.
DOI : 10.1007/s11661-998-0201-3

O. Dominguez, Etude de la compaction et du frittage de poudres nanométriques de Fe et Cu, UFR Scientifique d'Orsay, 1996.

L. Dupuy, Comportement mécanique d'un alliage d'aluminium hyperdéformé, Ecole DoctoraleMatériaux et génie des Procédés, 2000.

L. K. Falk, P. R. Howell, G. L. Dunlop, and T. G. Langdon, The role of matrix dislocations in the superplastic deformation of a copper alloy, Acta Metallurgica, vol.34, issue.7, pp.1203-1214, 1986.
DOI : 10.1016/0001-6160(86)90007-6

F. Greulich and L. E. Murr, Effect of Grain size, dislocation cell size and deformation twin spacing on the residual strengthening of shock-loaded nickel, Materials Science and Engineering, vol.39, issue.1, pp.81-83, 1979.
DOI : 10.1016/0025-5416(79)90172-1

E. W. Hart, Theory of the tensile test, Acta Metallurgica, vol.15, issue.2, pp.351-355, 1967.
DOI : 10.1016/0001-6160(67)90211-8

J. P. Hirth and J. Lothe, Theory of dislocations, 1982.

J. Y. Huang, Y. K. Wu, and H. Q. Ye, Deformation structures in ball milled copper, Acta Materialia, vol.44, issue.3, pp.1211-1221, 1996.
DOI : 10.1016/1359-6454(95)00231-6

K. V. Ivanov, I. V. Ratochka, and Y. R. Kolobov, Investigation of possibility to get superplastic state of nanostructured copper, Nanostructured Materials, vol.12, issue.5-8, pp.947-950, 1999.
DOI : 10.1016/S0965-9773(99)00274-3

Y. Iwahashi, Z. Horita, M. Nemoto, and T. G. Langdon, The process of grain refinement in equal-channel angular pressing, Acta Materialia, vol.46, issue.9, pp.3317-3331, 1998.
DOI : 10.1016/S1359-6454(97)00494-1

D. Jia, K. T. Ramesh, E. Ma, L. Lu, and K. Lu, Compressive behavior of an electrodeposited nanostructured copper at quasistatic and high strain rates, Scripta Materialia, vol.45, issue.5, pp.613-620, 2001.
DOI : 10.1016/S1359-6462(01)01071-5

H. Jiang, Y. T. Zhu, D. P. Butt, I. V. Alexandrov, and T. C. Lowe, Microstructural evolution, microhardness and thermal stability of HPT-processed Cu, Materials Science and Engineering: A, vol.290, issue.1-2, pp.128-138, 2000.
DOI : 10.1016/S0921-5093(00)00919-9

O. Johari and G. Thomas, Substructures in explosively deformed Cu and Cu-Al alloys, Acta Metallurgica, vol.12, issue.10, pp.1153-1159, 1964.
DOI : 10.1016/0001-6160(64)90095-1

O. A. Kaibyshev, B. V. Rodionov, and R. Z. Valiev, Peculiarities of dislocation slip during superplastic deformation of Zn-Al alloys, Acta Metallurgica, vol.26, issue.12, pp.1877-1886, 1978.
DOI : 10.1016/0001-6160(78)90100-1

H. S. Kim, A composite model for mechanical properties of nanocrystalline materials, Scripta Materialia, vol.39, issue.8, pp.1057-1061, 1998.
DOI : 10.1016/S1359-6462(98)00257-7

S. Komura, Z. Horita, and M. Nemoto, Influence of stacking fault energy on microstructural development in equal-channel angular pressing, Journal of Materials Research, vol.257, issue.10, pp.4044-4050, 1999.
DOI : 10.1557/JMR.1997.0173

Y. Konishi, M. Motoyama, H. Matsushima, Y. Fukunaka, R. Ishii et al., Electrodeposition of Cu nanowire arrays with a template, Journal of Electroanalytical Chemistry, vol.559, 2003.
DOI : 10.1016/S0022-0728(03)00157-8

K. Konopka and J. W. Wyrzykowski, The effect of the twin boundaries on the yield stress of a material, Journal of Materials Processing Technology, vol.64, issue.1-3, pp.223-230, 1997.
DOI : 10.1016/S0924-0136(96)02571-X

K. Konopka, J. Mizera, and J. W. Wyrzykowski, The generation of dislocations from twin boundaries and its effect upon the flow stresses in FCC metals, Journal of Materials Processing Technology, vol.99, issue.1-3, pp.255-259, 2000.
DOI : 10.1016/S0924-0136(99)00434-3

J. J. Lewandowski and P. Lowhaphandu, Effects of hydrostatic pressure on mechanical behaviour and deformation processing of materials, International Materials Reviews, vol.60, issue.3, 1998.
DOI : 10.1179/imr.1993.38.4.193

L. Lu, L. B. Wang, B. Z. Ding, and K. Lu, High-tensile ductility in nanocrystalline copper, Journal of Materials Research, vol.24, issue.02, pp.270-273, 2000.
DOI : 10.1016/0965-9773(93)90016-5

L. Lu, M. L. Sui, and K. Lu, Superplastic Extensibility of Nanocrystalline Copper at Room Temperature, Science, vol.287, issue.5457, pp.1463-1466, 2000.
DOI : 10.1126/science.287.5457.1463

S. Mahajan and G. Y. Chin, Twin-slip, twin-twin and slip-twin interactions in Co-8 wt.% Fe alloy single crystals, Acta Metallurgica, vol.21, issue.2, pp.173-179, 1973.
DOI : 10.1016/0001-6160(73)90059-X

T. Malis and K. Tangri, Grain boundaries as dislocation sources in the premacroyield strain region, Acta Metallurgica, vol.27, issue.1, pp.25-32, 1979.
DOI : 10.1016/0001-6160(79)90053-1

A. Mascanzoni and G. Buzzichelli, Electron microscopy evidence for a Frank-Read source operating from a grain boundary in alpha-iron, pp.857-860, 1970.

M. J. Mayo, R. W. Siegel, A. Narayanasamy, and W. D. Nix, Mechanical properties of nanophase TiO2 as determined by nanoindentation, Journal of Materials Research, vol.60, issue.05, pp.1073-1082, 1990.
DOI : 10.1038/330556a0

S. X. Mcfadden, A. P. Zhilyaev, R. S. Mishra, and A. K. Mukherjee, Observations of low-temperature superplasticity in electrodeposited ultrafine grained nickel, Materials Letters, vol.45, issue.6, pp.345-349, 2000.
DOI : 10.1016/S0167-577X(00)00131-2

A. Melander and K. Husby, Influence of the strain rate sensitivity of diffuse necking in tensile tests, Materials Science and Engineering, vol.46, issue.1
DOI : 10.1016/0025-5416(80)90194-9

B. Mingler, H. P. Karnthaler, M. Zehetbauer, and R. Z. Valiev, TEM investigation of multidirectionally deformed copper, Materials Science and Engineering: A, vol.319, issue.321, pp.319-321242, 2001.
DOI : 10.1016/S0921-5093(01)00975-3

O. V. Mishin, D. Jensen, and N. Hansen, Microstructures and boundary populations in materials produced by equal channel angular extrusion, Materials Science and Engineering: A, vol.342, issue.1-2, pp.320-328, 2003.
DOI : 10.1016/S0921-5093(02)00311-8

R. S. Mishra, S. X. Mcfadden, and A. K. Mukherjee, Analysis of Tensile Superplasticity in Nanomaterials, Materials Science Forum, vol.304, issue.306, pp.304-30631, 1999.
DOI : 10.4028/www.scientific.net/MSF.304-306.31

J. E. Morral and M. F. Ashby, Dislocated cellular structures, Acta Metallurgica, vol.22, issue.5, pp.567-575, 1974.
DOI : 10.1016/0001-6160(74)90154-0

L. E. Murr, Some observations of grain boundary ledges and ledges as dislocation sources in metals and alloys, Metallurgical Transactions A, vol.45, issue.3, pp.505-513, 1975.
DOI : 10.1007/BF02658408

M. Niewczas, Z. S. Basinski, and J. D. Embury, The deformation of copper single crystals

R. L. Nolder and G. Thomas, The substructure of plastically deformed nickel, Acta Metallurgica, vol.12, issue.2, pp.227-239, 1964.
DOI : 10.1016/0001-6160(64)90192-0

W. C. Oliver and G. M. Pharr, An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments, Journal of Materials Research, vol.XI, issue.06, pp.1564-1583, 1992.
DOI : 10.1557/JMR.1992.0613

S. Poulat, Etude par microscopie électronique en transmission des processus d'accomodation des dislocations extrinsèques dans des joints de grains de nickel, UFR Scientifique d'Orsay, 1997.

A. Rohatgi, K. S. Vecchio, G. T. Gray, and I. , The influence of stacking fault energy on the mechanical behavior of Cu and Cu-Al alloys: Deformation twinning, work hardening, and dynamic recovery, Metallurgical and Materials Transactions A, vol.2, issue.1, pp.135-145, 2001.
DOI : 10.1007/s11661-001-0109-7

A. Rohatgi, K. S. Vecchio, G. T. Gray, and I. , A metallographic and quantitative analysis of the influence of stacking fault energy on shock-hardening in Cu and Cu???Al alloys, Acta Materialia, vol.49, issue.3, pp.427-438, 2001.
DOI : 10.1016/S1359-6454(00)00335-9

P. G. Sanders, A. B. Witney, J. R. Weertman, R. Z. Valiev, and R. W. Siegel, Residual stress, strain and faults in nanocrystalline palladium and copper, Materials Science and Engineering: A, vol.204, issue.1-2, pp.7-11, 1995.
DOI : 10.1016/0921-5093(95)09928-X

I. N. Sneddon, The relation between load and penetration in the axisymmetric boussinesq problem for a punch of arbitrary profile, International Journal of Engineering Science, vol.3, issue.1, p.47, 1965.
DOI : 10.1016/0020-7225(65)90019-4

A. W. Thompson, Yielding in nickel as a function of grain or cell size, Acta Metallurgica, vol.23, issue.11, pp.1337-1342, 1975.
DOI : 10.1016/0001-6160(75)90142-X

T. Ungar, J. Gubicza, P. Hanak, and I. Alexandrov, Densities and character of dislocations and sizedistribution of subgrains in deformed metals by X-Ray diffraction profile analysis, Mater. Sci. Engng, pp.319-321274, 2001.

T. Ungar, A. Révész, and A. Borbély, Dislocations and Grain Size in Electrodeposited Nanocrystalline Ni Determined by the Modified Williamson???Hall and Warren???Averbach Procedures, Journal of Applied Crystallography, vol.31, issue.4, pp.554-558, 1998.
DOI : 10.1107/S0021889897019559

T. Ungar, S. Ott, P. G. Sanders, A. Borbély, and J. R. Weertman, Dislocations, grain size and planar faults in nanostructured copper determined by high resolution X-ray diffraction and a new procedure of peak profile analysis, Acta Materialia, vol.46, issue.10, pp.3693-3699, 1998.
DOI : 10.1016/S1359-6454(98)00001-9

R. Z. Valiev, E. V. Kozlov, Y. F. Ivanov, J. Lian, A. A. Nazarov et al., Deformation behaviour of ultra-fine-grained copper, Acta Metallurgica et Materialia, vol.42, issue.7, pp.2467-2475, 1994.
DOI : 10.1016/0956-7151(94)90326-3

R. Z. Valiev and T. G. Langdon, An investigation of the role of intragranular dislocation strain in the superplastic Pb-62% Sn eutectic alloy, Acta Metallurgica et Materialia, vol.41, issue.3, pp.949-954, 1993.
DOI : 10.1016/0956-7151(93)90029-R

R. Z. Valiev, I. V. Alexandrov, Y. T. Zhu, and T. C. Lowe, Paradox of Strength and Ductility in Metals Processed Bysevere Plastic Deformation, Journal of Materials Research, vol.25, issue.01, pp.5-8, 2002.
DOI : 10.1007/s11837-000-0127-8

H. Van-swygenhoven, A. Caro, and D. Farkas, A molecular dynamics study of polycrystalline fcc metals at the nanoscale: grain boundary structure and its influence on plastic deformation, Mater. Sci. Engng, pp.309-310440, 2001.

J. A. Venables, Deformation twinning in FCC metals, pp.379-396, 1961.

N. Wang, Z. Wang, K. T. Aust, and U. Erb, Effect of grain size on mechanical properties of nanocrystalline materials, Acta Metallurgica et Materialia, vol.43, issue.2, pp.519-528, 1995.
DOI : 10.1016/0956-7151(94)00253-E

Y. Wang, M. Chen, F. Zhou, and E. Ma, High tensile ductility in a nanostructured metal, Nature, vol.81, issue.6910, pp.912-915, 2002.
DOI : 10.1038/nature01133

B. E. Warren, X-ray studies of deformed metals, Progress in Metal Physics, vol.8, pp.147-202, 1959.
DOI : 10.1016/0502-8205(59)90015-2

G. K. Williamson and W. H. Hall, X-ray line broadening from filed aluminium and wolfram, Acta Metallurgica, vol.1, issue.1, pp.22-31, 1953.
DOI : 10.1016/0001-6160(53)90006-6

R. N. Wright and D. E. Mikkola, Deformation twinning: Time dependence and associated strengthening effects in shock-loaded Cu-8.7at.%Ge, Materials Science and Engineering, vol.53, issue.2, pp.273-283, 1982.
DOI : 10.1016/0025-5416(82)90061-1

V. Yamakov, D. Wolf, S. R. Phillpot, and H. Gleiter, Deformation twinning in nanocrystalline Al by molecular-dynamics simulation, Acta Materialia, vol.50, issue.20, pp.5005-5020, 2002.
DOI : 10.1016/S1359-6454(02)00318-X

V. Yamakov, D. Wolf, M. Salazar, S. R. Phillpot, and H. Gleiter, Length-scale effects in the nucleation of extended dislocations in nanocrystalline Al by molecular-dynamics simulation, Acta Materialia, vol.49, issue.14, pp.2713-2722, 2001.
DOI : 10.1016/S1359-6454(01)00167-7

C. J. Youngdahl, J. R. Weertman, R. C. Hugo, and H. H. Kung, Deformation behavior in nanocrystalline copper, Scripta Materialia, vol.44, issue.8-9, pp.1475-1478, 2001.
DOI : 10.1016/S1359-6462(01)00712-6

M. G. Zelin and A. K. Mukherjee, Analysis of the cooperative grain boundary sliding in terms of cellular dislocations, Philosophical Magazine A, vol.60, issue.6, pp.1183-1193, 1993.
DOI : 10.1016/0921-5093(93)90450-S

M. G. Zelin and A. K. Mukherjee, Geometrical aspects of superplastic flow, Materials Science and Engineering: A, vol.208, issue.2, pp.210-225, 1996.
DOI : 10.1016/0921-5093(95)10080-6

A. P. Zhilyaev, G. V. Nurislamova, B. Kim, M. D. Baro, J. A. Szpunar et al., Experimental parameters influencing grain refinement and microstructural evolution during high-pressure torsion, Acta Materialia, vol.51, issue.3, pp.753-765, 2003.
DOI : 10.1016/S1359-6454(02)00466-4