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In the boundary and interior of the grain, a number of rare elements and its compounds were dispersed.
Grain number per unit area increased by about more than doubled, and size of the grains are more uniform.
In the boundary and interior of the grain of the nugget with Ce or Er, a number of fine particles were dispersed.
The second phase strengthening In the boundary and interior of the grain, a number of Al3Er, Al4Ce and its compounds Al-Al3Er, Al-Al4Ce were dispersed after adding Er, Ce in the nugget.
Fine grain strengthening The grains of nugget are significantly refined after adding rare earth elements.

The average grains size is 7-6 index, when welding without the TMF influence and the average grains size of the weld metal corresponds to 8 index, with separate inclusions of grains with 7 index when welding with the TMF influence.
These data are summarized in monographs [1, 2] and given in a significant number of publications [3-5].
Besides in a number of publications, it is shown that the transverse magnetic field (TMF) use also allows to obtain the above-mentioned positive effects.
Thus, the data on the TMF influence on the weld crystallization in arc welding are few in number.
Electromagnetic stirring and grain refinement in stainless steel GTA welds.

Additionally, the number and size of β-Mg17Al12 particles were found to increase with the addition of a small amount of calcium.
While a number of techniques have been shown to be capable of producing fine grain sizes in AZ31, the addition of small amounts of calcium has been found to have a significant impact on dynamic recrystallization during hot rolling[4, 5].
During hot rolling, grain refinement by a factor of 10 to 80 times commonly occurs, and finer structures can be achieved in some Mg alloys by using a small number of high strain rolling passes after multiple cycles of rolling and reheating.
This is because each pass causes the grains in the metal to be further deformed and elongated, leading to a refinement of the microstructure and an increase in the number of dislocations within the grains.
However, the limitation to the too many number of passes is that material becomes brittle and prone to cracking.

The number and the density of surface defect were increased.
CURM then produced a large number of sub-grains.
With the strain increasing, dislocation cells increased in the number and reduced in the size.
Finally there are many sub-grains within the grain, the size of grains on the metal surface is smaller.
It needed greater resistance to transform, which played the role of grain boundary strengthening, Smaller grain size in the same volume needs the larger number of grains in the same deformation.

Superplasticity in Coarse-Grained Al-Mg Alloys E.
A number of mechanisms have been proposed for coarse-grained superplasticity [2, 5-7], although the actual mechanism has not yet been identified.
Grain size measurements were carried out to select suitably coarse-grained material (> 20 µm) for the tensile testing.
These etched samples were then examined optically to determine the grain size, amount of grain boundary movement, and deformed grain shape.
The arrows in Fig. 6(f) indicate the presence of the newly formed grains at the boundaries of the deformed grains.

For smaller number of turns (N = 1), the Hv increased with distance from the disk center.
The ultimate tensile strength, UTS, and the total elongation, EL, were plotted in Fig. 8 as a function of number of turns.
Some continuous-recrystallized grains were observed.
Fig. 8 Mechanical properties of HPT-processed iron as a function of number of turns.
Langdon: Ultrafine Grained Materials III, TMS, ed. by Y.T.

According to the results, the original <10 1 0> fiber texture of the extruded AZ61 alloy became disintegrated and a new texture progressively developed with increase in number of ECAP pressing.
The effect of grain size strengthening was examined in the ECAPed Mg alloys with different grain size but with a very similar texture.
An image analysis program of Matrox Inspector 2.2 was used to determine the grain size distribution and mean grain size from optical micrographs.
This ineffectiveness of grain-size reduction on strength agrees well with Mukai et.
Summary Texture modification during ECAP has a great influence on the strength of Mg alloys because HCP metals have limited number of slip systems.

The transverse (sub)grain size and the number fraction of high-angle (sub)grain boundaries were about 0.2 µm and 75%, respectively.
It should be noted that the size of these fine grains is comparable with the transverse (sub)grain size in the cold worked sample.
The annealing behaviour looks similar to a normal grain coarsening with a grain growth exponent about 6.
The numbers indicate the misorientations in degrees.
The polygonization rapidly developed at an early annealing and resulted in the evolution of almost equiaxed ultra fine-grained microstructures with a grain size of about 0.3 µm, which is close the transverse size of highly elongated deformation (sub)grains.

Role of Mo on Static Recrystallization Kinetics in Coarse Grained Nb Microalloyed Steels B.
Although there are different rolling mill configurations, in a high number of industrial plants there are no roughing stands and the thin slab goes directly to the finishing mill.
The following parameters were quantified at each condition: the recrystallized volume fraction (X) and the grain size distributions of both recrystallized and unrecrystallized grains, being the grain size defined as the equivalent area diameter provided by the analyzer.
The number of intercepts per unit length of boundaries between recrystallized and unrecrystallized grains, , was measured to calculate the migrating boundary area per unit volume between recrystallized and unrecrystallized regions, , according to Hilliard [[] J.E.
In the table the following measurements are included: the mean austenite grain size (Dmean), the critical grain size (Dc, defined as the value for which at least a 10% of the volume fraction of grains have a greater size than that critical grain size), the amount of accumulated strain and the fraction of as-cast grains that remain before transformation.

Grain yield has been reported that significant correlation with grains per plant [6], number of filled grains per panicle, number of productive tillers per square meter and 1000 grain weight [7].
Data were collected: number of tillers plant-1, plant height, number of panicle, panicle length, number of seeds, seed length, seed width, 100 grain weight and grain yield.
Rice 102 Rice 231 and Rice 199 were the most of number of grains per panicle as 171.00, 163.33 and 159.37 grain per panicle respectively, and Rice 263 was the lowest in number grain (57.33 grain per panicle).
Both size of the grain and number of grains per panicle decide the panicle weight.
The number of grains/panicle is a critical that determines the grain yield.