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Strain vs. number of cycles to failure is described by the Basquine-Coffin-Manson curve shown in figure 1.
The number of cycles to failure vs. first loading unstabilized strain value curve Ꜫp1N is constructed.
For a grain size index (ASTM number) of 7-8, corresponding to a 32-22 [mm] grain size according to the ASTM E112 standard, the number of grains at the specimen gage cross section was 187-272.
Thus, according to Henning and Vehoff’s model of gage section for a small-scale tensile specimen, the material properties were not affected by the number of grains [20].
The average number of cycles to failure and standard deviation were calculated.

The easiest method for determining m is to calculate the slope of the log � - log�& sigmoidal plot in the vicinity of the point of inflection assuming steady state loading and grain size to be constant [2].
Yoder and Weis [4] carried out a lead patenting operation to achieve grain refinement in eutectoid steel and reported a 140% elongation.
The same material was subjected to the heat treatment as outlined in Fig. 1, to induce grain refinement after which the specimens were tested in the same testing conditions as mentioned above.
The initial microstructure exhibited a granular pearlite microstructure as shown in Fig. 7(a) exhibiting a grain size in the range 1-5µm.
The SEM micrograph shown in Fig. 7(c), illustrates a ferrite grain structure of 1- 10µm with hypereutectoid iron carbides of 0.5-5µm.

Only small number of study focuses on pure rutile TiO2 MAO coating.
Grain size of the coatings Groups A B C D E Grain size (nm) 54.2 35.9 22.4 25.0 65.7 Fig.2 Grain size of the coatings Experiments has proved that pure rutile TiO2 MAO coating can be produced by adding Al(OH)3 into electrolyte.
Fig.4 shows the relationship between micro-hardness and grain size.
When dislocations move to the grain boundaries, obstacles of grain boundaries must be overcome.
After these processes, the deformation is transferred from one grain to another.

The grains have different sizes and shapes, tip radius and depth of cut.
The grain tip was set to the lowest position.
The number of cracks that are not filled with metal is noticeably less.
The number of d-electrons increases to 5.
When niobium is micro-scratched, the metal also sticks to the grain tip.

Controlled quantity of water (about 6% for a start) was then added and the mixture left in the desiccator for about one hour to allow water to penetrate the mixture grains.
Results and Discussion Four randomly selected specimens of the air-dried samples were then subjected to preliminary classification tests including grain size distribution and Atterberg limits.
For grain size distribution tests on the selected specimens, about 300grammes was soaked in water for 24 hours and thereafter washed through No. 200 sieve.
For standard liquid limit tests on the selected specimens, about 50 grammes of oven-dried materials passing sieve number 40 (with 425 microns opening) was mixed with a known quantity of water, mixed thoroughly and left in the desiccator for about one hour to allow the water to penetrate the entire grains.
Lime addition neutralizes the acidity in the air-dried chicoco soil, releasing additional moisture within the mixture, pulling apart the soil grains, leading to lower density.

Table1 Number of sample and its treatment process Sample Numbers Blade model Acid corrosion etching of Co time R（ C2H2/O2） Deposit time 1# YG16 20min 1 40min 2# YG16 20min 1 60min 3# YG16 20min 1 80min 2.4 Experimental Methods XL-30FE scanning electron microscope and EDAX energy dispersive spectroscopy are used to observe the surface morphology, cross-section morphology and micro-determination of chemical composition.
Table2 YG16 carbide surface state of before and after the flame deposition Sample Numbers Blade model Deposition time Size of WC grain before deposition （nm） Size of WC grain after deposition （nm） Consist of phase remark 1# YG16 40min L（001）=50.01 L（100）=33.10 L（001）=64.96 L（100）=42.97 WC D D: Diamond G: Graphite CNT: Carbon nanotubes 2# YG16 60min L（001）=50.01 L（100）=33.10 L（001）=58.18 L（100）=28.62 WC D G 3# YG16 80min L（001）=50.01 L（100）=33.10 L（001）=71.38 L（100）=46.67 WC G CNT Co (a) deposition times 20mins (b) deposition times 40mins (c) deposition times 60mins Fig 3.
By high power surface morphology observe a large number of fibrous composite carbon nanotubes cover carbon composite ball surface, shown in 4(d).
Sample 1, sample 2 cross-section micrograph shows that ball diamond columnar grain growth and film / substrate interface, a small amount of columnar grains exist little gap and micro porous.
Spherical diamond pins in fine-grained WC substrate.

To describe more complex behavior of different polycrystalline materials may be necessary to increase the number of levels, for example, with an introduction of an intermediate scale level for describing the mechanism of grain boundary sliding or an introduction of microlevel for explicit description of the defect structure evolution.
However, it should be noted that increasing the number of levels in the model leads to a significant increase in resource consumption.
As long as there is a slip system (or set of slip systems), where the dislocation slip activate criteria is fulfilled, the material during plastic deformation will be forced to use a smaller number of slip systems than is necessary in order to fully choose the prescribed deformation.
Fig. 3, on the left, shows a typical dependence of the critical additional stress due to (5), at all slip systems randomly selected grain, on the intensity of deformation.
Left: typical dependence of the critical additional stress due to (5) for the slip systems of any grain; Right: the stress - strain diagram for cyclic deformation of polycrystalline aggregate with terms (5) and (6).

Characteristics of the investigated ZrO2 materials 1)- three point bending Material ZTA-1 ZTA-2 ZTA-3 A 2 MgO-PSZ Strength (σσσσ4b) [MPa] 454 + 45 550 + 70 515 + 80 395 + 60 705 + 501) Commercial IKTS IKTS IKTS Commercial Phase Composition Corundum c-ZrO2 t-ZrO2 m-ZrO2 88.2 + 0.6 4..1 + 1.5 5.8 + 1.5 1.9 + 0.4 89.5 + 0.6 2.3 + 1.5 8.1 + 1.5 0.1 + 0.2 90.2+ 0.6 2.5 + 2 7.0 + 2 0.2 + 0.2 75 + 2 25 + 2 Al2O3 Grain Size D(50) [µm] 2.04 1.49 0.9 ZrO2 Grain Size D(50) [µm] 0.84 0.48 0.25 Results and Discussion The observed mass losses and residual strength of the materials in hot 1N H2SO4, 1N NaOH and in water at 200 °C are given in Fig. 1.
Depending on the composition of the grain boundary phase the corrosion behavior of the silicon nitride ceramics can alter significantly.
The different behavior can be explained by the different stability of the grain boundary phases [1-3].
The corrosion behavior of the ceramics strongly depends on the composition of the grain boundary phase.
They would like to acknowledge the financial assistance received from the BMWi and the AiF (contact number AiF Nr.: 12130 BR) and from the DFG (contact number He 2457/4 - 2 ).

The microstructural design containing a multilayer structure with a large number of interfaces has enhanced hardness as well as remarkably improved tribological performance [8].
Figure 2 shows the HRTEM images of CrAlTiCN films with the current of 0.5, 1.5 and 2.5 A. the incorporation of C into CrTiAlN produces MeN nano-crystal grains and amorphous carbon, With increasing current of graphite target, the MeN grain size (size less than 8 nm) of multilayer films gradually decreases and the amorphous carbon appeared as a single layer, as shown in Fig. 2(b) and (c).
Due to the increase of a large number of interfaces, the microhardness would be enhanced with decreasing the periodical thickness of multilayer films.
From literature [14], when the grain size was less than approximately 10 nm, further reduction in grain size would lead to decrease in microhardness, especially the microhardness of amorphous material was lower than the nanocrystalline material.
The multilayer structure and fine grain size of CrAlTiCN films are responsible for the enhancement of microhardness in the films.

Fortunately, it was found that scandium could significantly improve the strength and recrystallization temperature of Al-Mg alloy, owing to the presence of coherent, finely dispersed Al3Sc precipitates that can be obtained at a high number density, thus preventing the dislocation motion [3,4].
The grains have been elongated along the working direction in all of the materials.
The fine Al3Ni particles arrayed along the grain boundary in 0.5 Ni alloy (Fig. b).
In Fig. 1(d), mass Al3Ni phases can be found at some grain boundaries
Fig. 2(c) shows intergranular corrosion progresses along certain grain boundaries.