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Some of them are: the type, size and number of inclusions, type of shielding atmosphere during welding, cooling rate, type of filler, welding heat input and other [6].
The microstructure of the weld metal consists of austenite grains with formed boundary proeutectoid and intergranular polygonal ferrite (PF) which are formed along the austenite grain boundaries during cooling of the austenite.
Ferrite formed along grain boundaries in the form of intergranular discontinuous layers is boundary polygonal ferrite (PF).
It can also be formed within the austenite grains with constant thickness as hypo-eutectoid or intragranular ferrite.
In the austenite grains of the weld metal (WM) acicular ferrite (AF) is dominant.

Segregation of the main elements distribution of the grain boundaries differs from one another.
a c d e f 250μmwred Fig. 1 Backscattered electron image (a) and EDS main elements distribution in the as-cast alloy: (b) Cu, (c) Mg (d) Mn, (e) Fe and (f) Zr A considerable number of coarse continuous non-equilibrium eutectic phases and intermetallics are presented in the interdendritic region and grain boundaries (Fig. 2).
But elemental solubility distribution grain boundary is larger than intra-granular.
Upon the homogenization temperature of 510 °C, the grain boundaries become thinner and clearer.
The results show that a large number of Al3Zr particles had been precipitated in the alloy.

This system has gradients in the number densities along the direction in the presence of a constant external magnetic field B=.
In the steady state, the charge neutrality reads: , Where , , and are the unperturbed dust, ion and electron number densities, respectively, and is the unperturbed number of charges residing on the dust grain measured in units of electron charge.
is the dust grain number density normalized to .
On the DA timescale, the electron density and ion density are in local themodynamic equilibrium and their number densities obey the Boltzmann distributions (2) (3) Where , with being the electron-temperature.

From the SEM observation, the grain connectivity became weak with smaller plate-like grain for x > 0.025 Yb concentration resulting in the decreased of Jc.
The pattern shows that with increasing substitutions of Yb, the peaks from Bi-2223 phase have decreased in number and intensities.
The Yb substitution samples in Fig. 2 (b)–(e) shows small plate-like grain result from presence of Bi-2212 phases.
Therefore, Jc for the Yb substituted samples dropped because of the weak grain connectivity and the increasing of porosity.
The features of the grains were observed via SEM with the grains degraded to form smaller plate-like rain structure indication of Bi-2212 phases.

Since the counting process does not start until a chunk candidate appears in all bloom filters, the frequency should add E(X) (the expect number of occurrence before a chunk passes the parallel filtering) to correct the estimation bias. 4.2 Two-stage Chunking This step contains a coarse-grained CDC chunking and a fine-grained frequency based chunking.
First, the coarse-grained CDC chunking algorithm chops the byte stream into large-size chunks.
(b) It should not be re-chunking when a chunk’s frequency is high after the coarse-grained CDC algorithm.
(m represents the size of the bit array for bloom filter, n represents the amount of data chunk, k represents the number of hash functions).
Certainly, there are many questions that need further research, for example, how to set the value of b0, b1 and the number of bloom filters to achieve better performance.

If grain-boundary diffusion is responsible for the atomic transport, the expression for the strain rate is where Dgb is the diffusion coefficient along grain boundaries and δ the grain-boundary width.
The grain-boundary contribution to the creep rate varies as , which indicates that it becomes more important for smaller grain size.
We suggest that grain-boundary diffusion controls Newtonian creep for small grain sizes.
Although creep behaviour is usually studied by uniaxial stress, deformation takes place on a number of slip systems.
For smaller grain size grain-boundary diffusion is presumably the process that controls Newtonian creep.

For the milled gear a very fine grain structure can be seen.
The grain structure of the gear produced by lateral extrusion is also fine.
The number of load cycles are shown on the horizontal axis.
Both gear-variants show fine grain structures.
The analysis showed that the hardness have the highest influence for small numbers of load cycles.

The processing maps are generated from the flow stress data as a function of temperature, strain rate and strain using the procedure described earlier and maps for a large number of materials have been developed and compiled.
Grain size correlations.
At low temperature, the microstructures of elongated grains is dominant, a small amount of dynamic recrystallization sub-grains distribut along the deformated grain boundary (Fig.5a); with the temperature increased, a lot of dynamic recrystallization grain form nucleus and grow along the boundaries of deformed grains, Microstructures translate complete crystal grain (Fig5b).
Strain rate will not only affect the nucleation of recrystallized grain,but also has affect grain growth process(Fig.5c and Fig.5d).
(4) With the temperature increased, a lot of dynamic recrystallization grain form nucleus and grow along the boundaries of deformed grains, Microstructures translate complete crystal grain.

And the grain size reached 15 μm.
As can be seen from Fig. 4 (b). α, there were a large number of pores as the sintering temperature climbed above 900 °C.
In addition, the grain size of the LS pebbles was much smaller than that of the LSC.
The grain size of LS pebble sintered at 950 °C was 2.6 μm (Fig. 4 (b).β), while the grain size of LSC pebble sintered at 800 °C was 15 μm (Fig. 4 (a).2) which was almost 6 times the size of the LS pebble.The lithium carbonate can be responsible for the differences (grain size and density).
Big diameter, small grain size, and high density usually present high crush load.

Many submicron SiC particles (average grain size was 0.9μm approximately) were located along the grain boundaries of ZrB2.
The migration of grain boundaries was blocked and the grain growth of ZrB2 was inhibited due to the distribution of submicron SiC particles.
In addition, some smaller SiC particles (average grain size: 200~300nm) also appeared in the ZrB2 grains (indicated by white arrows in Fig. 1b), which was called intragranular nanostructure.
If the migration speed of ZrB2 grain boundary was faster than that of nanosized SiC, the nanosized SiC particles tended to be trapped in the ZrB2 grains during sintering, and formed the intragranular nanostructures.
The intragranular nanostructure could form a large number of sub-grain boundaries.