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It is also significant to emphasize the importance of admissible aggregate grading and tolerable shape of grains.
There must be sufficient but not an exceeding number of particles smaller than 0.25 mm contained in aggregates for good workability of fresh concrete and impermeability of hardened concrete.
The microstructure of cement matrix and the interfacial transitional zone between the cement matrix and the surface of aggregate grains decides on the water tightness of concrete.

After reaction, remove the plate,wash it by a large number of de-ionized water, drying stand.
(b) (a) Fig.1 (a)SEM images of the Dy-doped TiO2 nanotube array;(b)15000-fold amplification 2.1.2 XRD Analysis Figure 2 is XRD graph of Dy-doped TiO2 nanotube array pretreated with calcination temperature of 550 ℃.It can be seen that Dy-doped TiO2 nanotube array is mixed with grain of anatase and trace rutile, undoped TiO2 nanotube array is mixed grain of anatase and small rutile, Dy-doping inhibit transformation of anatase to rutile to some extent[6].

Here, on the assumptions that the reactant are equally mixed and even rank spherical grain, the original radius is r0, and the radius is r at t time.
Then, the mass change is (2) where is the grain number of per mass of BaCO3 , and is the density of BaCO3.

As time increased, titanium surfaces produced a number of pores with different size.
These Ca-P precipitators consisted both of clusters of the nano-calcium phosphate grains.
Concentration of calcium and phosphate in 2SBF is higher than that in SBF, more crystal nuclei of OCP easily formed on the porous-surfaces and grown to crystal grains.

Introduction Spark Plasma Sintering (SPS) is a newly developed rapid sintering technique with fast densification and minimal grain growth for preparing materials.
So the viscose flow causes the grain to shrink. αl, Tv and Ts are the thickness which can cause the viscose flow, the surface temperature and the inner temperature of the particles, respectively.
With the time decreases, the shrinkage neck number decreases gradually.

After reaction, removed the titanium plate; washed it by a large number of deionized water, drying.
The results showed that N affected the crystallinity of TiO2, hindered the growth of crystal grain and promoted the increase of specific surface area [5-6].
The N could hinder the growth of crystal grain and promote the increase of specific surface area References [1] Y.H.

Because of the differences in elastic properties of the tool and the work surface, the Fig.2 Diagram of the tool tip grain vibrating state abrasive is hammered into the work surface.
There are a large number of input parameters in the ultrasonic machining process which will have influences on machining efficiency, machined surface quality, achievable form accuracy.
These process parameters are implemented through reducing tool diameter, abrasive grain size, and vibration amplitude to the microscale.

Apparently, the wear resistance is closely linked to the limited number of slip planes in the HCP structure.
It is found that when ageing follows alloy quenching, a reduced number of HCP embryos participate of the martenistic transformation [14, 16].
Apparently, during alloy quenching a number of HCP embryos become active nuclei for the martensitic transformation giving rise to athermal martensite.
Apparently, the limited number of slip systems in the HCP matrix severely limits plastic deformation, thus promoting fatigue cracking.
Moreover, it is found that the amount of SIT e-martensite is strongly influenced by the alloy grain size, with increasing hardening rates at smaller grain sizes [32, 33].

For example, the determination of the depth of decarburization of metal materials [1] focuses on the deepest decarburization, the testing of non-metallic inclusions [2] focuses on the level of inclusions in the worst field of view, the testing of the maximum grain size level (ALA grain size) on the metallographic sample section[3] focuses on the largest grain size, the ultrasonic testing of wrought products [4] focuses on the largest defect, Charpy pendulum impact test [5] focuses on the minimum impact energy, and the tensile testing [6] focuses on the minimum strength and plasticity value.
2) The empirical cumulative probability Pi of each maximum value is calculated by Pi = i/(N+1), where N is the number of samples and N = 8. 3) In formula (1), let Y = (X-λ) / σ, then take two natural logarithms on both sides, then Y = -ln﹛-ln [F (X)]﹜, let the empirical cumulative probability Pi be the value of Gumbel distribution function F (Xi), and let Yi = -ln﹛-ln [F (Xi)]﹜, and then get the Yi of each maximum value in turn. 4) The average value of 8 extremums in Table 2 is 46.39mm, and the standard deviation is 10.82mm.
If the distribution test is not consistent, it should be considered to increase the number of samples or explore other types of extreme distribution.
[3] ASTM E930-99(2007) Standard Test Methods for Estimating the Largest Grain Observed in a Metallographic Section (ALA Grain Size)[S]
[9] ISO/IEC GUIDE 98-3:2008/SUPPL 2:2011Uncertainty of measurement — Part 3: Guide to the expression of uncertainty in measurement (GUM:1995) — Supplement 2: Extension to any number of output quantities[S]

Schäfer and Kaminsky identified the reason for the roughening in the grain size of the material [8, 16].
Dislocations of grains or groups of grains, that are oriented randomly, normal to the load direction cause the roughness change.
In free forming zones without contact between the sheet and tool, the surface roughens due to dislocation of grains in the microstructure.
The measurement points were numbered from one to ten in which the numbers from one to six apply to points on the punchside and points seven to ten are assigned to the dieside of the cup.
Ludwig, On the correlation between crytallographic grain size and surface evolution in metal forming processes, in: International Journal of Mechanical Sciences 52 (2010), 523-530 [21] I.