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The modern high-quality mineral admixtures and high-performance chemical admixtures give raise to the rapid development of concrete technology with a large number of research results came out [1-2].
For good workability, Bolomey insisted that the fresh concrete must maintain a certain number of micro-particles, and should extract P= 10% of the number of aggregate gradation.
Manufactured sand generally has rough surface, rich powder and grain-type multi-angular.
Compact durability Workability Grading of all levels Ultra-filled coefficient Grain type of all levels Volume stability Fig1.
As follow: This method is simple and convenient for an application, K1,K2,W/C affected by workability and strength depend on the types of concrete, while the P1,P2,r affected by grain shape, particle size, and grain composition are typical of aggregate. 3.

Hence, the workpiece should be heated up to the single-phase αMg temperature range by solution heat treatment to allow the αMg+Mg17Al12 eutectic to dissolve back into αMg, followed by producing a large number of fine Mg17Al12 precipitates [8] during aging.
This can be explained by the coalescence and abnormal grain growth (AGG) during 400°C solution heat treatment.
As shown in the microstructure of the tensile-tested samples in Fig. 3, deformation twinning is detected in large-grain samples but not in small-grain samples.
Therefore, the effects of grain size on strengthening may be partially offset by the fact that large αMg grains are more likely to form tension twinning.
Ÿ Deformation twinning is detected for large-grain AZ91 samples after the tensile test

The results showed that the average grain sizes increased with increasing sintering temperatures.
The average grain size distribution was checked by linear intercept method from SEM micrograph.
The phase analysis was carried out based on the Joint Committee on Powder Diffraction Standard (JCPDS) file number 81-0042 and 36-0340 [15,16].
These patterns could be matched with a JCPDS file number 81-0042 [15].
The average grain size increased with increasing temperature as shown in Fig. 4.

We used number A to define (110℃/2h+157℃/3h) as the first stage of thermal exposure.
And the whole thermal exposure is defined as number B.
The grain boundary precipitates possess different sizes.
Their number decrease to 5.3% and 3.6% respectively.
The average size of grain boundary of T74 alloy is bigger than T79+B alloy.

This is illustrated in the austenite grain of Fig. 1a; two variants of martensite of equal size will display the same calculated texture as that in which one variant is a hundred times larger in volume than the other.
Of the 24 possible orientations of martensite that can form in any given grain of austenite, some will be favoured and others opposed since they do not comply with the stress - in other words, variant selection occurs.
Therefore, the sign and magnitude of the mechanical driving force depends on the orientation of each of the 24 variants of martensite in any given grain of the parent phase with respect to the external stress.
Fig. 2: ∆GMECH/∆G versus the number of most favoured variants per grain (n), for a variety of steels
An important point to note is that during transformation under stress, the martensite-start temperature is different for each of the 24 crystallographic variants in any given grain.

A number of typical junctions between the laths after LCF are considered.
Heat treatment was performed so that to form large austenite grains, heating to 1250˚C for 2h, quenching to water and annealing at 200˚C for 1h.
However, TEM examinations showed that further increase in the number of fatigue cycles, deformation occurs by twinning as well as by slip (see Fig.4).
Thus, one may arrive at the conclusion that these packets belong to one and the same austenite grain.
Here should be supposed that this intrusion occurred during plastic deformation caused by the neighboring packet from another austenite grain.

This is a dynamic germ-grain model [5], used to model situations in which nuclei (germs) are born in time and are located in space randomly, and each nucleus generates a grain evolving in time according with a given growth law.
The important parameters[7] in a Matern cluster process are: a)λp, the mean number of clusters per unit of area; b)nc, mean number of points per clusters and c)R, the cluster radius.
Again, for spherical grains growing with a constant velocity, G, and site-saturated nucleation.
The mean total number of nuclei per unit of volume is simply λpnc = 1250.
Figure 4 shows the influence of the number of nuclei per unit of area on the kinetics of the transformation nucleated on random parallel planes.

We drew three lines (①②③) in the photograph and counted the interceptions of grains.
The length of grains was calculated by using the following equation: where the L is the length of the line (mm), nL is the number of grains, is the average size of the grains (mm), nL is the total number of the number of interceptions and 0.5 which is a modification number for broken grains on the periphery.
We used the average size of the grains in this work.
Do not number your paper: Tables.
The equations have to be numbered sequentially, and the number put in parentheses at the right-hand edge of the text.

The conventional swaging method, using a number of relatively small, multi-passes, was employed to realize 20% to 60% reduction in cross-sectional area.
SEM images and analysis of impact fracture From the four modes of fracture in tungsten alloys, namely W/W grain boundary (contiguity) fracture, tungsten particle cleavage, matrix/W interface and ductile fracture of matrix, the W/W grain boundary fracture appears to require the least amount of energy.
This is due to the intrinsic weakness of the grain boundaries, making them an easy crack propagation path.
When the deformation degree reaches 40%, the shape of tungsten grains is becoming ellipse.
The fracture mode is cleavage fracture of tungsten grains, as shown in Fig.4.

The highlight areas may be caused by the segregation of Y and Nb, which have larger atomic numbers.
(c) that there exist many small grains, a few large grains, and the air holes are much bigger.
In a word, the grains are nonuniform distribution.
(b), there are many large size grains, and almost no air hole.
The grain size of YTiNbO6 ceramic increases, with the sintering temperature rising. when sintered at 1380°C, as shown in fig. 5(b), the larger size grains increase and the smaller size grains become less, the porosity is rarely and the grain size distribution uniform, then densification degree increases.