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To find main cause of increasing of void volume fraction, the increasing number of voids was classified by size.
When strain level is 10% for fracture, micro void nucleated mainly at ferrite-martensite grain boundary and in ferrite grain concerning both materials.
(a) Material A (b) Material B Fig. 7 Micro void number classified by size in each material.
Fig. 8 Micro void number classified by nucleation site in each deformation stage.
This is caused that micro void nucleates not only grain boundary but in the main grain.

The cast materials have an equiaxed grain structure with an average grain size of ~140µm, and constituent particles are mostly decorated in the interdendritic regions and grain boundaries [10].
Characteristic size parameters of constituent particles, equivalent diameter d and number density were measured by the image analysis software Image-J.
This is expected since the C1-3 samples have a weaker potential for concurrent precipitation and have limited number of pre-existing dispersoids.
A large number of recrystallized grains, with equiaxed shape, are already present after a short annealing time of 500s.
As these recrystallized grains are growing, their close to equiaxed shape further confirms that the recrystallization process is only weakly affected by the pre-existing dispersoids and concurrently precipitated ones, both of which are limited in number.

(2) where Γ is the Gibbs-Thomson coefficient, R is the dendrite tip radius, Pei is the Peclet number for i, mi is the liquidus slope, C0,i is the initial concentration for i, ki is the partition coefficient for i, ζc(Pei) is a function of the Peclet number, Iv(Pei) is the Ivantsov solution and Ghkl is the average temperature gradient near dendrite tip
Material and Experiment Procedure The dimensions of each small-scale plate are 30mm (length) ×15mm (width) ×5mm (thickness) for a number of bean-on-plate laser welding.
This location is contributory factor of problematic stray grain formation.
This phenomenon explains why (001)/[110] welding configuration more easily initiates stray grain formation.
This location overwhelms stray grain growth and essentially facilitates single- crystal γ-dendrite growth.

The best room temperature tensile strength and ductility were attained in specimens which had been heat treated to relieve stresses produced by the fabrication process but that had a minimum number of recrystallized grains [3].
Recovery should pronounce the <110> texture in rolling direction (RD) while recrystallization will generate a different texture [5] and reduce the number of single-fold dislocations thus decreasing the tensile ductility.
During recrystallization the first recrystallized grains in alloy A appear in bands at the grain boundaries between former grains.
Due to the smaller grain size and the less pronounced layered grain structure in the rolled state recrystallized grains occur with higher number, are smaller and more evenly distributed.
The average grain size has increased due to strong grain growth.

Grain refinement generally decreases the thermal conductivity because phonons can be scattered at grain boundaries.
The number of rotations imposed on the disks was 5 turns.
Fig. 4 shows an optical micrograph for the VBM disks indicating grain sizes of several mm.
The flow of the deformation by HPT is traced from the changes in grain shapes as shown in Fig. 5.
(2) The grain size was reduced significantly from mm to µm order by applying HPT

With the transformation of co-doped inhibitors’ content, the grain growth is inhibited and the grain size achieves 490 nm at 0.4% Cr3C2 / 0.3% NbC.
With its exceptional hardness, wear resistance and high mechanical strength, it is becoming very desirable for a number of applications.
Until now, the most successful way of controlling the WC grain growth is the addition of small amounts of WC grain growth inhibitors.
(a) (b) Fig. 1 SEM graphs of cemented carbides: (a) 0.4%Cr3C2+0.3%NbC; (b) without inhibitor As shown in Fig. 1, larger numbers of dark zones which may represent pores can be observed in (a) than (b), and the phenomenon will be studied in the next work.
Secondly, the presence of inhibitor NbC / Cr3C2 at the WC–Co interface prevents the transfer of the phase and stops the WC grains connected and growing, which results in the increased amount of the single WC grain, ensuring the inhibition of both normal grain growth and abnormal grain growth of the WC grains [14-19].

For example it was reported that for BaTiO3 the dielectric thickness will become less than 1um in a very near future and the number of layers could exceeds 1000 [2].
Much additional peaks were resolved when the grain size became large.
Especially, the peaks, corresponding to wave number ranging from 400 to 600 cm-1, became too broad to be observed.
Compared with photo frequency the FWHMA values are more sensitive to the grain size.
The corresponding critical grain size was about 22-33nm.

Recently, there has been significant attention on the fabrication of ultra fine-grained steel consisting of the finer ferrite grain size [2].
Finer ferrite grains can form due to the more nucleation site being available.
As a result, the ferrite grain is quite finer for the specimen 2.
This was attributed to the refinement of the ferrite grain size.
When cold heading steel is deformed, dislocations are produced in numbers proportionate to the degree of deformation.

The grains in the heat-affected zone were relatively coarse.
It is seen that the microstructures of AZ31B magnesium alloy were mainly fine dynamic recrystallization grains, and there were small amount of coarse grains and elongated grains (Fig. 1 (a)).
Therefore, the crystal grains in the HAZ were relatively coarse (Fig. 1 (b)).
It is seen that there were a large number of dimples on the fracture surface of base metal, and the fracture mode belongs to the ductile fracture (Fig. 3 (a)).
The grains in the heat-affected zone were coarser, and the grains in the thermo-mechanical affected zone were relatively small and deformed.

Both the grain and grain boundary conductivities have been determined as a function of temperature in the range of 773-973 K.
The ohmic resistance value has been considered as a complex number which contains series of various electrical elements.
The grain and grain boundary separation can be slightly identified at lower temperature (673-773 K).
Influence of Grain and Grain Boundary on Electrical conductivity Though the sample has a larger grain size (~1-2µm), the ionic diffusion through grain boundaries (GDC-GDC and Ni-GDC, NiO-NiO) is more sluggish than grain interior.
Therefore NiO-GDC grain contacts are to be expected in Ni (50:50) composition at lower temperature (673-873K) whereas number of homo contacts can be higher than hetero contacts at higher temperature (823-973K) range in which grain resistance (RGi) may be predominant over boundary resistance (Fig. 9).