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The prepared lanthanum tungsten has amorphous structure, the thermal stability is good, the powder grains present oval shape, and the diameter of grain is less than 1μm, the powder grains reunit partially.
Fig.3 The SEM photograph of lanthanum tungsten Fig.4 The SPM photograph of lanthanum tungsten The SEM photograph of lanthanum tungsten powder indicated that the product presented sponginess, the powder grains reunited partially, so and particles were big.
DSC curves indicated that there was an endothermic peak from 60℃ to 150℃, because vaporizing of free interstitial water molecules between the particles absorbed a great number of heat.
The prepared lanthanum tungsten has amorphous state structure, the thermal stability is good, the powder grains present oval shape, and the diameter of grain is less than 1μm, the powder grains reunit partially.

Introduction Reinforced concrete silo is an upright container used to store granular materials such as grain, coal, cement and so on.
In this paper, taking the silos of one grain storage for instance, the dynamic response analysis of a single column-supported silo and that of group silos are carried out and contrasted through finite element method.
The Establishment of the Finite Element Analysis Models Taking the representative silos of one grain storage for instance, the prototypes of column-supported reinforced concrete group silos are arranged as 3×4 layout.
The total height of the silos is 40m, including the length of the column 8m and the grain-install height 32m.
The seismic performances of group silos are better than those of a single silo, and with the increase of the silo number, the lateral rigidity of the group silos increase greatly. 3.

Grain boundaries affect the oxidation resistance.
A darker zone at grain boundary (resp. a brighter in grain area) corresponds to a lower (resp. a higher) flux of backscattered electrons due to a lower (resp. a higher) atomic number (Z) element located at grain boundary (resp. in grain area).
Since thermal oxide grown on Ni–based alloys have mainly contain Ni, Fe, and Cr [5–7], chromium, which has the lowest atomic number among these three elements should be the major element forming oxide at grain boundary.
The elemental analysis at grain boundary entirely differs from that of the ordinary grain.
In addition, both samples accordantly showed that the number of components in the layers certainly is higher than two.

Then make lapping circle 20 Dividers, divided into 100 areas totally, marked with numbers within every regions from inside to outside, in order to calculate the number of various regions of trajectory points accurately(as shown in Figure 1).
Given mme 100= , trajectories of a single diamond grain are obtained under different reduction rate )/( wpkk ωω= .As shown below, abrasive disk and silicon wafer with the same direction of rotation ( wp ωω , are positive) (red line represents the abrasive disk , the green line represents the silicon chip ).
Lapping trajectory has a relationship with reduction rate k ,the direction of the initial time point p (conclude pr and pθ ), abrasive disc or the speed of rotation of workpiece,eccentricitye [3,4,5]. 1) Speed ratio k decided the number of "petal"of lapping trajectory. 2) The location of the initial time points p :with pr increases, the maximum radial of lapping trajectory increases,that is, the closer the initial time point p to the edge of lapping disc,the greater its lapping trajectory of "petal".The minimum of lapping trajectory is relate to the level of the initial time point A close to the center point 'o of workpiece, the closer the initial time point A to the point 'o ,the smaller"mahogany"of lapping trajectory;phase position pθ have no effect on the shape of the track,it will only make the phase change.pieces of pictures in Figure 3 is a single diamond grain trajectory in the silicon surface, and it can't respect the lapping uniformity of abrasive to silicon
chip.The following depend on the different angle and radius select 50 abrasive grain evenly on the abrasive disc and simulate to the uniformity of silicon chip processing.
For swing plane lapping method,when pω and wω with the same shift, 3=k as the critical value,the standard deviation of the number of abrasive trajectory point QS is minimum, as 3number of abrasive trajectory point QS increases slowly,it is explained that the abrasive trajectory uniform is getting worse; while 3>k , with k increases,the standard deviation of the number of abrasive trajectory point QS with a significant increase,the distribution of abrasive trajectory getting more and more uneven;with k tends to infinity, QS is increasing,but the tend of the increase is slowly

But the serious dendritic segregation and the distribution of a large number of Mg-RE compounds in cast Mg-Gd-Y-Zr alloys are likely to lead to poor plasticity.
Extension of heat preservation time will lead to decrease of dendrite segregation, fuller dissolve of compounds at grain boundary and within grains at the same temperature.
But grain growth and coarse grains will appear when temperature is too high and heat preservation time is too long.
Meanwhile, as the insulation time extends (Figure 2(f)), some of the grains become bigger and the grain boundaries become blurred.
Influence of Homogenization on Properties of the Test Alloy Vickers hardness number of the test alloy can confirm the structure change to a certain degree.

The stress to cause the fracture of grain Mg-rich dendrites arises from the externally imposed stress, which are generated to maintain the deformation continuity across the grain-matrix boundaries.
N is the cycle number and C is a constant.
Fig.3(b) shows the relationship between the crack length and cycle number in low-cycle fatigue.
It decreases gradually until disappear with increasing the cycle number.
However, at elevated temperatures, the fatigue crack is able to cleavage the α-Mg grain of cast magnesium alloys, accompanied by the slips on the surface of α-Mg grains.

The amounts of Ca, P and the Ca/P ratio of the coatings formed on Ti with surface nanostructure were greater than those on coarse-grained Ti.
Refinement of grains, resulting from shot peening, is quite obvious in the shot peened condition.
Relatively more distinct nanosize grains, with increased number density and more uniform distribution, were seen in the shot peened annealed condition.
The USP-treated samples demonstrated an enhanced performance compared with the coarse-grained Ti samples.
Superplastic behaviour of ultrafine-grained Ti6A14V alloys.

When the grain is smaller, the number of grains available for sliding in the same direction also increases.
That means the slip is realized in more grains and the plastic deformation increases too.
It is assumed that with increased number of ARB process cycles, the bonding of the layers could become unstable.
The unit of hardness given by the test is known as the Vickers Number (HV) of the Duramin Micro-Hardness Tester.
The hardness of two materials is boosted with increasing number of ARB cycles.

It is well recognized that many properties of polycrystalline materials are determined by grain boundaries (GBs).
Grain-boundary diffusion plays a key role in such practically important processes as Coble creep, sintering, diffusion induced grain boundary migration (DIGM), various discontinuous reactions, recrystallization and grain growth.
In Chapter III Professor Valiev presents experimental data demonstrating the super-strength and “positive” slope of the Hall-Petch relation when passing from the micro- to the nanostructured state in a number of metallic materials subjected to SPD.
The role of grain boundaries in the achievement of high performance of these materials is discussed.
In Chapter XIII by Professor Molodov recent research on grain boundary migration is reviewed and the results of experimental efforts over recent years to study the motion of grain boundaries under various driving forces are analyzed.

The CaCO3 decomposition and elongated hibonite grains produced micropores.
Ltd., number of cells: ~ 8 ppcm (pores per-linear cm)) was chosen as the replication template.
The elongated grain formation caused grains interlocking; which causing entrapment of micropores between them, thus pore closure mechanism was difficult to achieve [15].
(grey: Al2O3 grains, light grey: CaAl12O19 grains, white: YSZ grains) c.
The coarser YSZ grains significantly improved the compressive strength.