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For instance, maximal grain-diameter equal to 0.16mm in the third group of stable 1 means that all grains in the specimens of the soil pattern were below 0.16mm.
It is thought that the influence of maximal grain-diameter on shear strength indirectly reflects the influence of grain-diameter range and grain grading.
The growth of maximal grain-diameter results in wider grain-diameter range and poorer grading to Gravel silty clay used in the experiment.
In contrast, the decrease of maximal grain-diameter results in narrower grain-diameter range and better grading.
The authors think that big grains grow constantly in number and so cohesion decreases while maximal grain-diameter enlarges; the change of internal friction has sensitivity because internal friction is determined by the irregular overturn movements of big grains on shear zone and the overturn movement of every big grain is different, hence shear strength has sensitivity to the change of maximal grain-diameter.

Also the acoustoplastic effect changes the kinetics of both dislocations and vacancies in the grain structure so that new secondary phases may precipitate in the vicinity of grain boundaries which are usually free of them and thusly possess lower strength.
It is common to identify three structurally different zones in the FSW joints on hot-rolled aluminum alloy sheets as follows: fine-grain stir zone (SZ) formed by the rotating pin, thermomechanically affected zone (TMAZ) with elongated coarse grains oriented with respect to metal flow in the SZ, heat affected zone (HAZ) and base metal (BM) with grains elongated with respect to rolling direction (Fig.2).
It follows from the results in Table 1 that mean solid solution SZ grains of both samples are of almost the same size.
The microhardness testing shows that UAFSW sample has more uniform distribution of hardness numbers across the zones (see Table 1) as compared to the FSW one and therefore this weld seam is more balanced in terms of strength.
At the same time the mean size of S-phase particles in FSW sample is lower by a factor of 1.7, i.e. these particles are distributed in higher number of grains.

AFM studies indicate that the grain size and surface roughness increase with the film thickness.
This is mainly due to the increase in average sizes of grains caused by the increase of film thickness coming from the increasing number of laser pulses.
Average diameter of grains and surface roughness of CdS thin films CdS thin films Avg.
This means that as the number of laser pulses increases the bandgap reduce.
AFM images indicate that the microstructure of the films surface consist of spherical shaped grains.

The first number indicates the SiC content and the numbers after the Al and SiC indicate the average particle sizes.
If N/NoD≈1, the initial number of particles is equal to the number of dilatation steps.
Characteristically such a value is obtained in case if the number of grains decreases quickly under the influence of the dilatation at the beginning.
If the number of grains is N=50…400 in the image, this value will not be changed by some separate particles.
The hardness as a function of a) the RPS b) the Al grain sizes (the number being in front of the SiC indicates its quantity and the number being after it indicates the particle size in µm).

This process, while being expensive to implement due to high tooling and raw material costs, saves a significant amount of money over the life of an airplane program due to greatly reducing the number of detail parts, which reduces the amount of expensive assembly that is required.
This monolithic technology will be used to reduce part count as well as the number of fasteners, assembly time, and weight all of which lead to cost savings for the product.
This fine grain material will also diffusion bond to standard grain alpha-beta alloys, as shown in Fig. 8, at 775 °C using the same time and pressure conditions [8].
These standard grain alloys typically require about 900 to 925 °C to fully diffusion bond.
At this temperature, the fine grain material will not only diffusion bond to itself but will also bond to standard grain alpha-beta alloys using the same time and pressure conditions.

The final microstructure is then related to the number of nucleation sites available at the onset of solidification and the subsequent solid/liquid conditions that control grain/dendrite coarsening.
These fragmented dendrite arms then act as embryonic grains to promote a grain multiplication effect, resulting in a refined, equiaxed microstructure.
For example, a grain size of a few micrometers can be achieved for a spray formed Al alloy billet as large as 300mm in diameter.
Phase field modeling indicated that the eight seed crystals fully developed into dendrite grains with many secondary arms and tertiary arms as showed in Figure 2 (c) during the initial solidification.
After an instant thermal shock of 1330 °C for 0.28 s, the majority of the secondary arms including some tertiary arms were remelted at their roots, and detached from the main trunk (Figure 2(d)), increasing the discrete solid particle number to ~70.

The {001} oriented grain centre gradually rotates around a <110> axis in small incremental steps when nearing the edge of the grain.
The role of variant selection and thus the number of product variants that actually appear after transformation still remains unclear.
The inverse pole figure (grey scale) in figure 3 shows a single layer of surface grains with specific grain morphology (elongated along RD).
The surface grains are very large in size (~200 µm) with irregular grain boundaries of which the majority exhibits the 3 (<111>60°) orientation relation which is generally connected with a reduced grain boundary energy [9].
grain 1.

The crystallization ratio and grain size of the silicon thin film become larger when D is higher.
Meanwhile, H2 dilution enhances crystallization of the films and makes the grain arrange orderly.
Fig.2 The dependence of crystallization ratio on different H2 dilution Fig.3 The dependence of grain size on D By calculation, the size of silicon thin film grain on glass substrate increases from 2.98 nm to 8.79 nm.
It is noteworthy that the grain size has a substantial increase in the D = 98% to 99%.
It will do harm to the crystallization and uniformity of silicon thin films when the powder fall onto the film surface.However, reaction of H2 and SiH2 can not only reduce the SiH2, but also generate re-used SiH4 due to the existence of a large number of H2.

There are a large number of small particles on the grain surface, the size of small particles is about100nm.
However, the morphology of biomorphic ZnO is not the ideal hexagonal prism, and there are a large number of small particles on the grain surface.
There are a large number of small particles on the grain surface, the size of small particles is about 100nm.

The model also explicitly tracks the precipitate populations at grain boundaries and in the grain interior.
There are a number of calibration parameters in the model that have to be found by fitting predictions to experimental measurements.
The calibration procedure is discussed in more detail elsewhere [1, 2].Grain Evolution Model The grain evolution model predicts the dynamically recrystallized (DRX) grain size and subsequent grain growth in the FSW--SZ.
These new grains will then be susceptible to grain growth, giving the final SZ grain size.
This grain growth is modelled using a simple classical grain growth model based on the mean grain size and a single (average) HAGB energy.