Search results

In UFG, slightly elongated grains with an average width of 300 nm were observed, indicating that the microstructure was in the process of evolving equiaxed grains.
Here, a high population of dislocations should still remain in the grain boundary areas as well as in the grain interior.
The mechanical properties before ECAP were 193 MPa tensile strength, 54 % elongation, and a Vickers hardness number of 64.
In addition to this, the whole surface observations of these specimens indicated that the damaged regions were formed at an early stage of cycling, and that the number and area of these regions slowly increased with further cycling up to a specific number of cycles, depending on the material and stress amplitude.
Once this specific number of cycles had been exceeded, both the number and area of the damaged regions showed a significant rise.

Here Si(i=1,2,3,4) is a variant of S orientation and CSi means the growth of a cube grain into an Si grain.
and indicated number of tiles and grains in the current specimen, respectively.
Here represents an increment of iteration number of the unit time process between the th and i th observation in the N th stage.
Grain size ratio (C/S) that is a ratio of a mean grain area of grains of component C to that of grains belonging to components S and B was 4.
Here, CSi , for example, means the growth of a cube grain into an Si grain.

In order to get fine grain, it is very important to study the correlation between fabrication process and the grain structures of foil stock.
The number of compounds below 1 μm decreases from S1a to sample S2a and sample S3a.
However, the number of compounds with size more than 2μm increases from S1a to sample S2a and sample S3a, which are listed in Table 2.
Table 2 Number of intermetallic compounds more than 2 μm per square meter in 0.55 mm foil stock Compounds size(μm) S1a S2a S3a 2-3 2101.3 6060.0 31351.4 3-4 253.2 580.0 4324.3 4-5 0.0 220.0 270.3 ＞6 0.0 0.0 270.3 Total 2354.4 6860.0 36216.2 Effect of Homogenization Conditions on the Grain Structures of AA8021 Aluminum Alloy Foil Stocks.
The grain structures of 0.55mm gauge foil stocks are shown in Fig. 5.

After 9 pass of MAF, grain size reduced to 2 µm.
Wear mass loss of MAF processed sample reduced, with increased number of MAF passes.
Average grain size of as-received sample was found to be 600 µm, with equiaxed grains, as shown in Fig 2 (a).
After MAF 3 pass, coarse grains are converted into finer grains and shear bands are formed in the place of elongated grains.
As the number of MAF passes increases, shear bandwidth decreases and dislocation density increases, this is the reason for the strength to increase and is called as grain boundary strengthening mechanism.

A Study of Carbon Nanotubes as Cutting Grains for Nano Machining J.
In this project, CNTs were directly used as cutting grains.
In this project, CNTs were directly used as cutting grains.
We fabricated a number of CNT wheels (Fig. 1(a)) for the experiments (Table 4).
CNTs can be used as cutting grains.

On the other hand, because the seepage in the slope body caused by rainfall carried the fine clay grains to the slope direction and the larger silt grains was left, then the laterite grains characteristic showed that the silt grains content increased and the clay grains content reduced with the slope altitude to increase.
Table 5 The density of slope’s soils number initial wet density / g/cm3 slope altitude / cm wet density / g/cm3 corresponding water content / % dry density / % Initial dry density / g/cm3 1 1.27 46 1.67 30.5 1.28 1.00 40 1.59 31.2 1.21 30 1.52 31.7 1.15 20 1.48 37.2 1.08 2 1.27 36 1.72 33.0 1.29 0.99 30 1.59 33.7 1.19 20 1.49 36.2 1.09 Table 6 The grain composition of slope’s soils number Initial silt content/ % location slope altitude / cm grain composition / % initial clay content / % silt content clay content 1 57.1 slope internal 46 61.4 38.6 42.9 40 63.3 36.7 30 61.6 38.4 20 61.6 38.4 10 58.7 41.3 0 59.6 40.4 slope surface 47 59.4 40.6 35 59.8 40.2 model tank front 0 64.4 35.6 tank surface -20 37.0 63.0 The change of shear strength of the laterite in the model slope under the effect of rainfall According to the above test results, the water content and density of the laterite in the each part of model slope have changed after a rainfall process.
These factors weakened the effect of the connection structure between the laterite grains and caused the connection force between the laterite grains to reduce, which would lead to the cementatory ability of the laterite grains to reduce.
In other words, the cementatory ability between the laterite grains was closely related to the density and the grain composition.
Then the raise of the contact point between the laterite grains made the embedding capacity between the laterite grains became stronger and the relative sliding between the laterite grains became very difficult.

This non-uniformity decreases when the number of turns is increased.
With higher number of passes, the grains become more equiaxed.
Figure 6 presents the grain size distribution of ECAE Ta subjected to different number of passes and different routes; note, an increased number of passes leads to decreased average grain size.
Therefore, the effective grain size with a higher number of ECAE passes should be even smaller.
Factors of SPD temperature, routes, number of turns in HPT or number of passes in ECAE, should be considered.

The size of grains and the crystal phase of copper oxide were controlled by the number of ALD deposition cycles.
As the number of ALD cycles increases to 750, the small grains become larger and merge with each other, as observed previously in the ALD growth of TiO2 on mesoporous Si [35] and TiN on SiO2 [36], or ZnO on InGaAs substrates [37].
The size of the copper oxide grains increases with the number of ALD cycles while, at the same time, the stoichiometry changes from predominantly CuO for small numbers of cycles to Cu2O for larger numbers.
In addition, for the small number of ALD cycles, the nanosized copper oxide crystallites are dispersed over the TiO2 surface (with the preferential nucleation sites at the TiO2 grain- boundaries), while larger grains of copper oxide cover most of the TiO2 surface for the larger number of cycles.
However, when copper oxide grains cover the most of TiO2 surface (750-cycle sample), the photocatalytic activity is greatly reduced, reflecting the reduction of the number of active TiO2 sites on covered surfaces.

During the past few decades, A Large number of research on engineering characteristics of coarse-grained soil have been carried out by many scholars abroad, and have obtained certain achievements[2-12].
Then, fine particles of coarse-grained soil fully fill into the pore between the large particles of coarse-grained soil.
In-situ compaction of coarse-grained materials[M].
Characteristic of dilatation of several kinds of grained soils[J].
Engineering properties and applications of coarse grained soil[J].

With increasing grain size, the activation of the nonbasal slip systems was limited near grain boundaries.
Journal Title and Volume Number (to be inserted by the publisher) � The compatibility effect is reduced with increasing grain size.
In the fine-grain sample, it is found to be grain-boundary sliding (GBS).
(a) grain-boundary region, (b) grain interior.
Journal Title and Volume Number (to be inserted by the publisher) [9] M.