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The evolution of the peak height is compared to the evolution of the grain diameter (Fig. 17).
Moreover, the peak goes up when the grain diameter is also increasing and therefore cannot be explained by a relaxation process linked to the grain boundaries. 400 500 600 700 800 0 100 200 300 400 500 600 700 temperature (K) peak Heightx10 4 0 50 100 150 200 250 300 350 400 grain diameter (µµµµm) 2,4 2,2 2,0 1,8 1,6 -8 -6 -4 -2 0 2 4 ed c b a 1000/T(K) ln (freq.
Evolution of the peak height and of the grain diameter as a function of temperature.
A number of tentative relaxation mechanisms are discussed in [37].
The numbers at the right of the curves (see Fig. 19) indicate the order of experiments and therefore this effect is reversible.

Fig. 6 Dielectric properties of BST thin films As we know, the dielectric constant of the thin film depended on the oxygen content, the chemical composition, the grain size, the interface and the crystallization of the film.
The grain size and the crystallization of the film were the two main factors affecting the dielectric constant.
With the prolonged annealing time, the grains grew larger and the film crystallized, so the dielectric constant increased.
With increasing the annealing time, the number of the grain boundaries that could hold up the defects decreased while the grains grew, as a result, the leakage current increased.

The originally smooth titanium surface was completely changed into grain of crystallization studded surface by the pre-calcification treatment, the grain sizes are on nanometer scale.
With the 12 h pre-Ca treatment, a small quantity of HAP grain appeared on the surface of titanium.
Scanning electron micrographs of titanium surfaces soaked in SBF for 96 h at 36.5℃ after the pre-calcification treatment for 48h Fig.2 Scanning electron micrographs of titanium surfaces soaked in SBF for 24 h at 36.5℃ after various periods of pre-calcification treatment. a large number of grains with the size from 10 to 20 nanometers.
In fact, a uniform nucleus layer on the surface subjected to 60 h of nucleation treatment showed higher growth rate than 12 to 48 h treatment in the early stage of the HAP crystal growth, due to the amount of grains of apatite is larger than others.

Hence, numbers of investigations have been mainly focused on the fluid delivery methods that make large volumetric flow-rate into the grinding zone in order to overcome boundary layer of air.
High fluid lubricating capacity reduces the wear on the grinding wheel by decreasing grain-workpiece friction, allowing the abrasive grains to maintenance of sharpness for longer periods and leading to lower wear of the wheel and attaining a high G-ratio value.
The MQCL technique led to lower roughness values than MQL grinding, probably because of the more effective lubrication and cooling of the abrasive grains at the work-tool interface.
The superior performance of the CBN grinding wheel was already expected, since the conditions of temperature and deformation are favorable with this tool, mainly due to the high thermal conductivity of the CBN grains.
The tangential cutting force was decreased with MQCL, possibly due to the presence of lubricant around the grinding wheel, providing better slipping of the grain at the piece-tool interface

The different loads were used so that the size of the indentations was similar, in order for the number and spacing between them to be approximately the same in each material.
Previous studies [1,2] have shown that, in friction stir welded aluminum alloys, the hardness variation and the corresponding inverse variation of the electrical conductivity are caused by changes in grain size due to processing.
Smaller grains increase hardness since there is a greater density of grain boundaries that act as an obstacle to the electron flow, reducing conductivity.
This is due to the competitive effects of grain size and precipitates, both size and distribution, that require further research.
· Mg alloy, however, shows a different behavior since FSP destroys and homogenizes the cast structure of the base material and a competitive effect of both precipitates size and distribution and grain size exists that needs further research

Fig. 1 shows microstructures of the samples. 1.75A1.75Y sample consisted of fine and equiaxed grains, whereas the grain size of 10A10Y sample was larger than that of 1.75A1.75Y sample and the elongated grains existed occasionally.
The number of indentations was 7 ~ 8 for each sample.
In the case of 10A10Y sample, all data showed larger dependence on the crack length than that of 1.75A1.75Y sample, which was attributable to the coarse and elongated grains in 10A10Y sample.
that KIc from the SEPB became larger than that from the Niihara's equation when the fraction of coarse and elongated grains increased in the Si3N4 samples [5].

Table 1 The grain composition of Interstitial Spall layer of coarse aggregate Grain size（mm） The percentage of the weight that through the following sieve(grain size) 53 37.5 31.5 26.5 19 9.5 Grain size（mm） 100 25～50 0～15 0～5 Table 2 The grain composition of gap filler Screen size （mm） 9.5 4. 75 2.36 0.6 0.075 Plasticity index Pass percentage（％） 100 85～100 50～70 30～50 0～10 The solid’s volume fraction test of interstitial spall Way and Step (1) To group crushed stone mixture according to uniform design table We should measuring the weight of big spall and small spall with platform scale first mix it thoroughly in text equipment .and then put the stone ships we need in the mould ,and fill the stone ship into the gap between spalls ,at last ,put the better deolian sand in text equipment , We need to devide the spall mixture into three parts to pour every compaction.It will make the spall mixture fill better and reach the compactness.
Table 3 The calculations of the volume fraction of solid The number of sample The thickness of sample h（cm） The volume of sample （） The volume of exhaust water（） Tth volume fraction of solid（％） 1 29.350 48776.838 36533.000 74.898 2 34.754 57728.479 45516.000 78.845 3 35.873 59610.685 45620.000 76.528 4 34.254 56924.797 42886.000 75.34 5 34.407 57179.393 42959.000 75.128 6 29.250 48609.215 35120.000 72.250 7 29.309 48707.264 36431.000 74.796 8 34.269 56950.058 43498.000 76.379 9 28.364 47114.306 34609.000 73.458 10 25.130 41762.378 31599.000 75.662 11 33.496 55638.866 42911.000 77.124 12 31.756 52748.621 39636.000 75.141 count the height of the sample .is (1) Attention;h-the height of sample ----the height of the sample of everywhere (2)count the volume of the sample .is = (2) Attention ;--the volume of sample.

As can be seen from the figure 2 (b), the mean grain size about 5μm was obtained, which is benefited to decrease the thermal conductivity.
The microstructures agree with the advantages of high-pressure synthesis, including the ability to tune rapidly and cleanly, restraining disorder and phase separation, introducing abundant grain boundary etc. [16] Fig 2.
The carrier thermal conductivity κe was cauclated by the Wiedemann–Franz law κe=LT/ρ where L is the Lorenz number 2×10−8V2K−2[9].The lattice thermal conductivity value κL, was estimated by subtracting the electronic contribution, κe, from the total thermal conductivity, κ.
As mention above, the SEM patterns show that the Ba0.372Co4Sb12 sample have very fine grain size, abundant grain boundary and especially many micro-pores inner the sample.
Combine Ba-filled with HPHT technology, fine grain size and micro-pores structure were obtained.

Manganese increases salt-water Table 1: Chemical composition of the used specimen Table 2: Grain size before and after heat treatment on each sample resistance in magnesium alloy [9].
Since grain size of each as-extruded sample was largely different as shown in Table 2, heat treatment was carried out for each sample.
Grain size after heat treatment was also summarized in Table 2, and there were no significant differences in their grain size.
As-Extruded Annealed 0.45%Mn 9.6 57.9 0.3%Mn 9.7 60.2 0.175%Mn 9 60.4 0.05%Mn 25.7 69 0%Mn 25.5 69.6 Grain Size, d [µm] In order to evaluate tensile properties, tensile test was conducted.
Adding excessive amount of manganese resulted in the increase in the number of coarse void nucleating particle

.%) [9-10], the chemistry of which differs from those of the commercial 9% Cr steels P91 and P92 in a number of aspects: 1) 3 wt.% Co is added; 2) W content is increased to 3 wt.% while Mo is totally removed and 3) C content is reduced to an extremely low level of 0.002 wt.% while the concentrations of V, Nb and N remain largely as they were in P91 or P92 [9].
The surface oxidised in air was rough with oxide grains protruding out to form a plate-like morphology, which coarsened substantially as oxidation time increased from 500 h to 3000 h (Fig. 3a and b).
The spot analysis by EDS showed that the oxide grains contained only Fe, Cr and O with the atomic ratio of Fe to Cr being approximately 1.68 and the O content 58.16 at.% (Fig. 3c).
The outer layer was the protrusion of the (Fe0.6Cr0.4)2O3 grains.
The height of such protrusions became larger at longer oxidation times as the oxide grains grew in size.