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(Numbers on right-bottom mean average grain size.) 　
With the increase of sintering temperature, tendency of prior β grain growth was confirmed.
Dimple pattern by ductile fracture are confirmed in Alloy compact and intergranular fracture due to grain growth was confirmed in M4 compact.
It means that grain surface is hardened by oxidization and b phase is difficult to transform to stress induced martensite which is definitely required for superelastic behavior.
Tensile strength and elongation of all sintered compacts at 1300°C were significantly decreased due to the prior β grain growth

Fig.1 Wear patterns of tool These observed tool wear phenomenon can be explained by a number of wear mechanisms such as adhesion, abrasion, diffusion and crack, as well as a result of a combination of above factors because it's very common for several tool wear patterns to be found simultaneously in the same tool and to have effect on each other.
WC loss may be individual grains, or agglomerates of grains when stresses become greater.
Attrition (removal of grains of tool material by the adherent chip or workpiece) was observed on the flank faces for all cutting conditions.
The evidence suggests that not only attrition was taking place, but also the tools were wearing by the removal of aggregates of grains, i.e. by spalling.
However it is significantly reduced by using the finest possible WC grain size in the tool material.

The average grain size of the material is 29mm, so one grain is included in the width and the thickness directions, and 2 or 3 grains are included in the height direction.
N=0 N=0.5 N=1 N=1.5 N=2 Number of cycles 10mm probe micropillar-shaped specimen 10mm Fig.5 Time-resolved photography during fatigue test with loading of 2mm displacement.

In recent decades, a large number of microwave dielectric ceramics have been developed for the potential application in the LTCC substrates.
Although glass phase may be observed in some of these samples, all the samples show mature grains about 1~2µm in average size.
It is easy to notice the typical plate-like grains and the sharp grain boundaries for the samples of x=0 sintered at 1300 o C and x=0.4 sintered at 1350 o C.

Introduction Mechanical alloying is one of the techniques that allows to produce nanocrystalline materials offering a variety of properties, which are considerably improved in comparison with those of conventional coarse-grained polycrystalline materials.
Mechanical alloying of Ni-Ti system have been the subject of a large number of studies.
At first stages of milling the effect of cold welding between Ni ant Ti powder grains is visible.
With the increasing of the milling time the formation of the large aggregates of grains is observed.

High band slope signal means defect free homogeneous lattice with low number of defects.
Fig. 2 Microstructure (cross section) of grit-blasted sample (EBSD – grain contrast).
Grit blasting results in a huge grain size reduction in the surface layer (microstructural analysis revealed a fine grain layer of about 30 µm thick – Fig. 2), an increase of dislocation density and a decrease in the mobility of the dislocations in the adjacent material.

It is very clear that the grain size has a significant dependence on temperature.
In Fig.3(a) the sample was calcined at 650°C can be observed a large number of smaller grains.
When the prepared powders treated at 1550°C (Fig.3 (b)) it is clearly observed the grain size is bigger and the prepared powders were partially sintered.

A large number of preparation methods of nano crystalline ZnO have been reported in the literatures [2-5].
Grain size and morphology of the as-synthesized powders were determined with transmission electron microscopy (TEM) using a JEM-2010 transmission electron microscope at the accelerating voltage of 75kV.
The grain size calculated for these powders from Scherres’s equation is about 30-40nm, which is not agree with the TEM results well (as shown in Fig.2).
TEM results indicate the as-synthesized ZnO is a mixture of granulous and rod-like morphologies, and the grain size is in a wide range, from about 10 to 100nm.

It shows that at a lower temperature, resistance is high, because of grain boundaries in crystal.
Impedances give us information about the grains and the grain boundaries.
Fig. 4 Average Impedance of Ce0.75Gd0.05Nd0.2-xCaxO2 The rate of successful hopping increased with an increase in temperature, as shown in the figure, represents less hindrance to charges at higher temperatures because the impedance decreases as the number of vacancies increases.

For a number of years, nanomaterials have been considered as a perfect solution to maintain the stability of different cultural heritage materials.
For enough years, a large number of nanomaterials has been applied to build up a desirable durability for carbonate monuments and a self-protection against weathering factors.
Determining the grain size of the formed NPs was available by changing the reaction parameters.
The FE-SEM micrographs on the samples showed assemblages of smooth grains together with large grains.
The microscopic images showed that the plaster grains which are masked with the white HAp-NPs (Fig. 4A).