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The platelet-like ZrB2 grains randomly dispersed in the equiaxed ZrC0.6 grains.
The formation of the developed platelet-like ZrB2 grains was the result of fine ZrB2 grain growth through the grain boundary diffusion and grain boundary migration during the sintering cycles.
The improvements of flexural strength and fracture toughness are associated with the microstructural development, the reduced number of large flaws or defects, relaxation of stress concentration at the crack tips and effective transfer of the load to the strong and hard platelet-like ZrB2 grains, which depended on the presence of excess Zr phase and sintering temperatures.
For the samples with equal to or greater than 16 vol% Zr (Fig. 6b), on the other hand, a large number of microcracks formed in the frontal process zone ahead of the Vickers indentation edge, in absence of main long crack.
In addition, microcracking behavior was observed only within the ZrC0.6 grains and the microcracks were arrested within the ZrC0.6 grains without propagation to the grain boundaries and/or to the neighboring platelet-like ZrB2 grains, as a result of a reaction of the residual radial tensile stresses in the ZrC0.6 grains and the residual compressive stresses in the ZrB2 grains.

The main reason of failure is that a large number of Cu particles passed through CoMoB grain boundary and reacted with Si substrate to generate Cu4Si with high resistance.
The main reason is that grain grew and surface stress released, which made atoms combine closely and CoMoB film changed densely and uniformly.
Cu particles passed through CoMoB grain boundary, arrived at Si substrate and reacted with Si to generate Cu4Si with high resistivity.
The main reason is that grain grew and surface stress released, which made atoms combine closely and the multi-film became dense and uniform.
XRD, FPP and AFM measurement results showed that the failure temperature of CoMoB is 600◦C and the failure mechanism is that CoMoB crystallized after high temperature annealing, a large number of Cu particles passed through CoMoB via grain boundary and reacted with Si substrate to generate Cu4Si with high resistance.

The toughness of the ceramic was observed to increase steeply when grains exceeded 0.52 µm, which has been identified as the critical grain size for toughening.
The modulus of elasticity or Young’s modulus is calculated using the experimentally determined resonant frequency (ASTM E1876-97, 1998) and the values were found to be consistent regardless of the number of test performed for each samples.
The open pores that existed within this 3Y-TZP sample retarded the grain boundary migration and thus, increased densities without significant grain growth.
At this stage, grain growth was more significant than densification.
&Fard F.G., Densification and Grain Growth of nanocrystalline 3Y-TZP During Two Step Sintering.

We employ the Lagrangian particle tracking (LPT) model to calculate pollen grain trajectories.
We set 2 types of initial distributions of pollen grains, and these are shown in Fig. 2(b), V1 and Vall.
For the type V1, pollen grains are initially distributed uniformly in the volume of 1.0 m3 around the air purifier.
The type V1 is useful to examine air purifier performance of removing pollen grains near the purifier.
The number of pollen grains is about 7,500 for both types.

Fig.3(b) shows that a great number of dislocations and subgrains are generated after the one impact LSP treatment.
In Fig.3c,d, It is shown that grain sizes have already been decreased to nano-magnitude.
The residual stress distribution is attributed to the grains refinement and work-hardening.
Grains-refinement and work-hardening have generated in TC11 titanium alloy after one impact, so the grains become smaller and the yield strength has been improved, which inhibits the further plastic deformation.
Work hardening and grain-refinement are the main factors improving the hardness.

These microstructures consist basically of equiaxed grains.
AZ31 sheet was composed of finer dynamically recrystallized (DRX) grains of about 16 μm, and LAZ531 sheet shows larger DRX grains of about 20 μm.
The EBSD map obtained from the LAZ531 alloy showed that a relatively larger number of grains were in blue or close to blue color.
Here, <> direction in most grains orientated parallel to the extrusion direction.
We referred to the recrystallization mechanism in the current work as rotational dynamic recrystallization because it gave rise to new grains with HABs [12, 13], also referred to as recrystallized grains.

The grain sizes of AZ31 magnesium alloy and composite were 223 and 78 mm, respectively.
Most TiB2 particles presented agglomerated along the grain boundary.
In detail, the average grain sizes both in transverse and longitudinal were about 20 mm.
Small particles of the TiB2 phase are distributed inside the grains.
As compared with Fig. 5a, the number of dimple decreased in the fracture surface of as-cast composites (Fig. 5b).

This process resulted in increased hardness and better grain refinement leading to improved wear properties.
Results and Discussion Microstructure: The microstructure of the as-received Hastelloy C-276 consisted of equiaxed grains with sharp grain boundaries and finely dispersed precipitates as shown in Figure 5 (a).
The LSA-1 (Figure 5(b)) exhibited the presence of a number of equiaxed grains with the size of the grains slightly bigger around the interface when Fig.4 Samples for corrosion test Fig.5 (a) Fig.5 (b) Fig 5(c) Fig 5(d) Fig.5 Micrograph of laser treated specimens in argon atmosphere (a) Base Alloy (b) 1.25 kW, 300 mm/min (c) 1.5 kW, 300 mm/min (d) 1.75 kW, 300 mm/min compared to the grains above the region indicating the upward increase in solidification rate.
It is concluded that the specimens with fine grains exhibited hardness above 400 HV compared to the specimens with coarse grains and columnar dendrites.
The hardness improved by 1.8 times indicating the significant effect of grain refinement on hardness. 2.

Fig. 2 (Frank-Read) Source Proliferation Process 1.3 Impact Mechanism of Alloy Elements Forming Grain Boundaries on Damping Capacity In magnesium alloys, metal compounds and other substances may form grain and sub-grain boundaries.
The alloy elements determine the proliferation space of proliferated dislocation loops by the size of magnesium alloy grains and sub-grains.The smaller the size is, the smaller the dislocation proliferation space is, so are the fewer proliferated dislocation loops in different dislocation sources, and the total length of movable dislocation lines is shorter.Meanwhile, the complicated dislocation network near the grain boundary will influence and restrict the movement of movable dislocations (dislocation sources) in matrix magnesium, thereby reducing the number of dislocation sources.Through the above conclusions and related theoretical analysis, reducing the average grain and sub-grain size of magnesium alloys can reduce the increasing rate of damping capacity on magnesium alloys. 1.4 Theoretical analysis and calculation of damping capacity in dislocation line tangled and multiplied stage Fig. 3 Plane geometry distribution of dislocation net As Fig. 3 shows, if the proliferated dislocation
ring is spreading evenly, set when the dislocation source actuate and began to proliferate, proliferation of the first dislocation ring radius as r，the density of dislocation source as p, the number of dislocation ring as n, the distance between two closed dislocation source as d since the dislocation ring is constant expanding outward under the pressure of alternating stress, the radius of multiplied dislocation ring is as the distance with the closed one born from the same source.
(2) Both the content and distribution of the alloy element decide the crystallite dimension and dislocation pinning of the magnesium matrix, thus affecting the number and equilibrium state of the dislocation sources and then largely influencing the damping property of magnesium along with the linear strain value (εa,εb and εc) at the critical point of all stages and the growth (change) rate of the damping property at the second, third and fourth stage.

Electrical fire happened in the number of all kinds of fire across the country have been first.
According to the ministry of public security fire station with the China fire Statistics Yearbook Data shows that the national fire was 13.3ten thousands in 2008 (Only statistics on month, do not contain the forest, grassland, army, fire underground part of the mine, the same below), including electrical fire 4ten thousands, accounting for 30.1% of the total number of fire. 1993 to 2007 years of 15 years, the national fire was 1.5276 millions, including electrical fire 37.37ten thousands, accounting for 24.5% of the total number of fire[1].Therefore, the fire investigation already has been the important content of fire control work in order to further fire prevention work and avoid big losses.
The transitional region of short circuited melt mark is obvious, the boundary of coarse columnar crystal grain and the edge of the melt mark appear in vertical direction, the needle-like crystals are the most in sub-boundary, and most of the microstructure of the transition region is the coarse equiaxed grain, and grain boundary perpendicular to the needle crystal within the interior tissue, no holes in it, that is the organization characteristics from melting area to the matrix present ferrite organization were transformed to widmanstatten structure by high temperature and then transformed to the as-cast organization, shown in figure5,6,7.
Due to the original ferrite wattle growth fastly to austenitic grain internal and the speed especially large in one direction, the form was parallel and sharp-angled shape, and in ferrite batten has residual austenitic, martensite and pearlite phase.Generally, a body were directly from the original ferrite austenitic grain boundaries stretch into austenitic grain inside; secondary tten ferrite grain formed in ferrite grain.