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In the study, improvements in the dispersion of the reinforcement were observed with increasing number of FSP passes, and finer grain sizes were produced with the addition of reinforcement particles.
It was also observed that the final grain size for various FSP passes were similar, as grain size is dependent on welding temperature [9].
Table 2 Grain size measurements Material and Process 6061 [13] μ-6061 n-6061[8] Average Grain Size (μm) 5.0 3.9 2.5 Standard deviation (SD) 3.5 2.3 2.0 Significant reduction in grain sizes were observed after FSP was performed.
The addition of micro sized particles further reduced the grain sizes.
The size of the reinforcement particles affects the average grain sizes.

When the welding current is more than 125A, the grains coarsen sharply, and the number of precipitates and defects increase obviously.
The microstructure of the WZ are equiaxed grains and the precipitation of second phase along grain boundary makes the hardness of grain boundary higher than the crystal, thus, the hardness of the WZ is higher; grain coarsening of the HAZ makes the hardness decrease during the welding thermal cycle.
(2) The FZ is composed of fine equiaxed grains.
The grain size of the HAZ is coarse because of overheating.
With the increase of welding current, the grain size of the HAZ remaines relatively stable.The BM consists of fine equiaxial recrystallization grain size

Fine-grained concretes are inferior to powder concretes not only in resistance, but also in durability (Fig. 4, 5).
This is primarily due to the large difference in conductivity, which increases as the grain size of the aggregate increases [10].
In cases where fine-grained concrete of the composition C:S=1:3 (by weight) is used, not all aggregate particles are covered with a cement shell [11], so there is a significant number of large pores in the contact zone between the aggregate and the concrete matrix, through which aggressive ions penetrate deep into the sample.
Concrete compositions with various types of aggregates and fillers can be arranged in a row as the corrosion resistance of concrete based on them decreases: powder concrete with quartz filler → powder concrete with marble filler → fine-grained concrete on marble filler → fine-grained concrete on quartz sand
Fine-grained concrete on marble aggregate is more resistant to magnesian corrosion than sulphate one

Average grain size and mechanical properties.
(a) At N= 2.0×103 cycles, Crack 1 was formed in Grain I.
Schmid factors of the basal slip system of each grain are indicated in Fig. 5, where the number of cycles, N, of each figure is the same as that of Fig. 4, and crack profiles were drawn by black lines.
Also, size of crack-initiated grains is much larger than the average grain size.
Acknowledgement Support of this work through a Grant-in-Aid for Scientific Research (C) from Japan Society for the Promotion of Science under proposal number 18K03837 (Head investigator: Professor Y.

The measured austenitic grain size is in the range 80~160 mµ .
Meanwhile, dislocation cells are elongated along deformation direction with the increase of cold deformation degree, the number of the dislocation cells rise and the sizes reduce.
Recrystallization will completely transform grains after cold transformation into a new equiaxed grain structure by nucleation and growth, and its mechanical properties will also change markedly.
The main reason of single austenite-grain obtaining ultrafine is that：due to the existence of deformation martensite, austenitic grains after severe cold deformation import austenitic-martensite(γ/M) phase boundaries.
Influence of Heat Treatment on the Grains of Cold Worked Austenitic Stainless Steel.

In order to clarify this problem, it is advisable to perform experimental research under conditions where the number of 'free parameters' affecting this transformation is minimized.
The range of potential disorientation angles was binned into intervals of 1.25o into which the number of disorientations across the recrystallization front corresponding to a given angular interval was counted.
The columns contain the explicit number (‘Counts’) of experimental axis in a class and the fractions after accounting for the differences in the areas of regions and the impact of crystal symmetry (‘Distr.’).
The results allows us to draw the following conclusions: · For Ni and Cu-2%Al and both initial orientations at the initial stages of recrystallization, the appearance of a specific number of new orientation groups of new grains was demonstrated.
This facilitates ‘the orientation stability' of a new grain growing into the as-deformed structure

The grain refinement can improve its ductility and formability.
The objective of the present work is to establish randomisation of texture to increase work hardening exponent by favourably orienting a large number of grains (texture) in AZ31 alloy to improve its stretch formability by promoting additional straining in thickness direction. 1.
Many techniques namely ECAP, HPT, and ARB can be used for grain refinement of bulk metallic alloys.
Microstructural observations indicated that decrease in grain size is favourable for increase in percentage of elongation while increase in grain size after deformation due to dynamic recovery favours improvement in stretch formability.
New deformation mechanism in fine grain Mg alloys.

Unfortunately, we could not find the rutile grain nucleated in the anatase particle due to very fast grain growth.
The numbers above indicates the particle size of anatase phase in diameter.
Unfortunately, however, we could not find the rutile grain nucleated in the anatase particle.
If the rutile grain is imbedded and trapped in the anatase particle after the phase transformation, the grain size of anatase should become smaller and smaller with the formation of rutile phase.
Unfortunately, however, we could not find the rutile grain nucleated or imbedded in anatase particle due to a very fast grain growth.

Usually these shape factors are dimensionless quantity, independent from the size of the grains and their position if the object contains a sufficient number of pixels [1].
Since during termomechanical rolling the ferrite grains form from rolled austenite grains it is expected that more of these ferrite grains more will have an orientation close to the rolling direction than the ferrite grains in the normalising rolled steels.
First the number of the intersections of the studied structure and the parallel test lines having different angles (Θ) has to be determined.
The number of the intersections as a function of the Θ angle gives a rose diagram.
In the picture numbers the 0 means the smallest while 5 the largest orientation of the pearlite.

The grain size was decreased with carbon content due to grain boundary pinning.
Equiaxied grains were formed regardless of carbon content.
On the other hand, in the C-added alloys, TiC particles existed inside of grains and at grain boundaries.
Although the linearity in Fig.7 is not good and the number of data is a few, σ0 and k are evaluated to be 165 MPa and 1322 MPa µm1/2, respectively.
The grain size reduction must be due to grain boundary pinning by TiC