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Both HPT and ECAP are capable of imparting Von Mises strains up to two figures, depending on the number of turns, passes, or die geometry.
In this respect, Figure 15 of that paper [6] summarizes a large number of investigations correlating flow stress with grain size, over the range of d = 5 - 1000 nm.
However, this mechanism has also been considered as probable in a number of cases in which grain size was in the S-mc/coarse range.
However, the number of recent investigations in S-mc materials pointing out to grain boundary sliding as an operative mechanism appears to be growing; for instance internal friction Figure 3.
The authors show that grain size reduction led to a decrease in grain boundary diffusion activation energy, thus shifting the onset of grain boundary sliding to lower temperatures.

Influence of finishing rolling variables on the austenite recrystallization and grain growth V.
The role of grain size and precipitation on final mechanical properties was discussed based on different strengthening mechanisms.
This paper seeks to address the influence of finishing rolling variables on the Nb precipitation state and its control on austenite recrystallization and grain growth.
The Nb precipitates retard or even suppresses austenite recrystallization leading to a pancake microstructure which offers a larger number of ferrite nucleation sites.
Fig. 1 Comparison between the grain sizes obtained after routes 1, 2, 3 and 4.

The main result obtained by the application of such technique is that the hyperbolic flow of grains is the nature way during deformation, as well; this hyperbolic motion is assisted by dislocations dynamics and self accommodation of grains.
The grain size of 42.10 µm was measurement by using the mean linear intercept technique [8].
Here twelve grains were selected and identified with a number in order to follow their trajectory during deformation process.
As it is shown in the Figure 2, in all pictures in the Figure 1, twelve grains were selected and identified with a number in order to follow their trajectory during deformation process.
Also, it is obvious that the displacement of each grain is a function of their position.

Microstructure analysis such as size, shape and number of precipitates were studied by Optical microscopy (OM) and Scanning Electron Microscopy (SEM).
The change in number of CuNi precipitates and CuNiZr precipitates led to an increase in hardness and wear resistance.
XRD analysis reported the reduction of β phase and showed that the grain size of ⍺ phase and β phase were refined.
It was found that grain size of CuBeZr alloy was not changed after DCT process and the average is around 36µm.
However, bigger average precipitate size at longer immersion time caused by more number of big precipitate developed.

The 300-500 nm grain size has been reached (see Fig. 7).
As a result of TE, the grain refinement to submicron level has occurred (see Fig. 8).
This fact allows us to increase considerably the number of patients which can be operated in order to insert such implants.
Zhu: Producing Bulk Ultrafine-Grained Materials by Severe Plastic Deformation.
Symp. on Ultrafine Grained Materials, eds.

According to EN ISO 643 was rated by number G = 7 / 8.
Ferritic grain size was G = 7.5 to 8.
Ferritic grain size was G = 9.5.
Ferrite grain size is quite similar in observed regions and according to EN ISO 643 was rated by number G = 9.
Ferritic grain size varied between number G = 7.5 and G = 9.

a b Fig. 2 shows equiaxed grains in TP-100-1 and TP-325-1 extrudates after extrusion and 825 o C anneal for 30 minutes.
The grain size was similar to the starting powders, (Fig. 1 and Fig. 2).
There was also subgrain structure within the extrudates that consisted of a needle phase within grains and an intergranular phase, Fig. 3.
Contrast due to low atomic number elements was detected within the needles and at intergranular locations that could not be explained by oxygen, nitrogen or boron levels greater than those in the matrix, Fig. 3.
Backscatter electron micrograph of TP-325-1 extrudate after annealing at 825 o C for 30 minutes showing low atomic number element contrast from needles and intergranular particles.

That model has been applied to grain boundaries as well as to interfaces in phase transformations.
It was thus evident that the sharp interface model should only be regarded as a first Journal Title and Volume Number (to be inserted by the publisher) 3 approximation.
They considered the attraction without any detailed modeling of the properties of the grain boundary.
Instead, the driving force originates from cold work if the material is deformed or from the interfacial energy of a curved grain boundary, which is curved in such a way that it puts the parent grain under a pressure.
Journal Title and Volume Number (to be inserted by the publisher) 5 Comparison The two approaches for a binary system can be compared by taking the difference between Eqs. 9 and 4.

Air-dry density, oven-dry density, basic density, shrinkage, swelling, parallel-to-grain compressive strength, parallel-to-grain tensile strength, modulus of rupture (MOR),modulus of elasticity(MOE) ,impact toughness were analyzed.
Materials and Methods Sampling methods, numbers of samples and general requirements for physical and mechanical tests have been followed by GB standards (SAC, Standardization Administration of the People's Republic of China) throughout the study.
Parallel-to-grain compressive strength, parallel-to-grain tensile strength and impact toughness were determined according to GB/T 1935-2009, GB/T 1938-2009 and GB/T 1904-2009 standards, respectively.
Information on the testing of Alnus formosana wood Test Properties Number of specimens Dimensions of specimens* Standards Density,air-dry, basic 20 20×20×20 GB/T 1933-2009 Shrinkage 20 20×20×20 GB/T 1932-2009 Swelling 20 20×20×20 GB/T 1934.2-2009 Modulus of elasticity (MOE) 35 300×20×20 GB/T 1936.2-2009 Modulus of rupture (MOR) 35 300×20×20 GB/T 1936.1-2009 Parallel-to-grain compressive strength 35 30×20×20 GB/T 1935-2009 Parallel-to-grain tensile strength 35 370×20×15 GB/T 1938-2009 Impact toughness 35 300×20×20 GB/T 1904-2009 * Longitudinal × radial × tangential direction (mm × mm × mm) Results and Discussion The results obtained on the physical properties of Alnus formosana wood are shown in Table 2.
The parallel-to-grain compressive strength of Alnus formosana wood averaged 41.575 Mpa.

Recently, due to increasing interest in nanosized systems a number of works in which appreciable changes of structural phase transition characteristics such as temperature and latent heat upon decreasing grain size have been reported experimentally [7-8].
Let us qualitatively estimate the effect of the mean-field reducing suggesting the concentration of JT - centres is diminished on the value that is linearly proportional to the volume of surface layer: ( )R�� JTJT /31 δ−= ∞ , where δ is an effective width of this layer, R is a grain radius, ∞JT� is a number of JT-ions per unit volume of the macroscopic-size crystallite.
The characteristic dependence of the JT deformation value upon the grain size is depicted in Fig. 2.
The latter results in changes of the orbital state of JT-ions and, as a consequence, in a decrease of their number in the sublattice where the ions have orbital degeneration.
On increasing the activation (and, consequently, on decreasing grain size) the number of ions in 'outlaw' positions has to be increased.