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The results show that, compared with the darker regions with lower atomic number, regions with larger atomic number are lighter in secondary electron composition contrast image.
The atomic number of W is 74, while the average atomic number of active material is 17.9 (below 20).
When characterizing microstructure of cathode materials using secondary electron image, the small bright grain (d) is observed.
The composition of the grain is analyzed by EDS, as shown in figure 4, the results show that the small bright grain is composed of C, O, Ca and other elements, neither cathode base nor active material, but impurities.
In the backscattered electron image of the cathode, the small bright grains are similar with active material in contrast.

(a) true strain : 0.25 (b) true strain : 0.5 in terms of the resolved shear stress and the shear modulus as G)(2 E 2 og τ = (6) Grains having a high stored energy are likely to nucleate and become dislocation-free grains by a dynamic recrystallization.
If P is larger than a random number between 0 and 1, a deformed grain will be a dislocation-free grain.
After uniaxial compression to true train, ε=0.04, the c-axes of many grains are aligned with the RD.
As true strain increases to ε=0.12, the c-axes of nearly many grains are aligned with the RD.
At the higher strains, it is clear that new dislocation free grains are nucleated along the former grain boundaries.

The morphology of the equiaxed grains was approximated by ideal spheres.
Next, equiaxed grains were forming in the bulk melt.
The nucleation process has been described by the conservation of the number density n of equiaxed grains in the numerical model.
The grains finally settled in the bottom of the test mould.
The morphology of equiaxed grains is approximated by ideal spheres.

Introduction There is much current interest in producing metals with very small grain sizes.
However, processing bulk aluminium alloys to sub-micrometer grain sizes is rather difficult, and normally the smallest grain sizes achievable through conventional thermo-mechanical means are ∼15-20 µm [1-4].
Several investigations have shown that, during deformation, grains in polycrystals subdivide into many small crystallites, each having a crystal orientation rotated toward neighbouring and to the original grains.
The requirement of a small and stable grain size is usually achieved by using either two-phase alloys or materials containing precipitates that impede grain boundary mobility and thereby restrict the development of grain growth.
This is primarily due to a more diffuse and larger number of fine Al3(Sc1-x,Zrx) dispersoids, which more effectively pinned boundaries, compared with Al3Zr dispersoids.

Ti is one of typical micro-alloying elements, while refining grain, Ti can facilitate precipitation strengthening.
It can be seen from the Fig.1, the microstructure of test steel is made of polygonal ferrite and acicular ferrite, ferrite grain occurs relatively coarse with the final rolling temperature 900°C (Fig.1a), and at 850°C (Fig.1b), the ferrite grain is uniform and fine, due to test steel rolling at lower temperatures, no phase transformation of γ grains are elongated, while grains have a large number of deformation bands and dislocation.
The more the nucleation points are, the refiner α grain will be.
That is all because of the ferrite refined grain strength promoting and Mo, Ti composite precipitation hardening.
At the final rolling temperature 850°C, the grain of ferrite is uniform and small.

Magnetic properties of Nd2Fe14B magnets are greatly improved if a strong crystallographic texture is achieved, namely, the direction of the c-axis of any grain is along the magnetizing direction.
Penetration of X-ray in Nd-Fe-B magnets is rather shallow to obtain a correct function of the grain-orientation distribution in a bulk material.
The number of a sample indicates a number of impulses of a magnetic field, applied to the sample powder at the stage of texturing.
The patterns of the textured samples comprise strong reflections (002), (006) and (008) indicative of a preferential orientation of the c-axes of the Nd2Fe14B grains athwart to the flat surface of the tabloid.
The number of a sample means the number of magnetic field impulses applied to the sample.

A limited precipitation of chromium carbides and nitrides at the grain boundaries has been detected in both grades.
Different phases have been observed by SEM examination of polished samples, using the backscattered electron (BSE) signal, on the basis of atomic number contrast effect: the ferrite appears slightly darker than austenite, while the secondary phases would appears lighter.
The SEM operated at 25 kV; the BSE detector was set to maximize the atomic number contrast, allowing ferrite, austenite and other phases to be identified.
The same grain boundaries precipitation was observed after soaking times longer than 40' at 650 °C, while at 750 °C the first grain boundary precipitation has been detected after a 20 min treatment (Fig.1a) and can still be observed after 20 h (Fig.1b).
The nitride precipitation is evident just below the austenite grain boundary, as it has moved towards the austenite (ferrite) giving the precipitation inside the austenite grains.

LBW joint (Fig. 1(d)) contains finer grains (7um) in the weld region as compared to FSW and PCGTAW joints.
The average grain size of magnesium grains in FSW joint is about 13um and the PCGTAW is 38μm.
Fig.2(d) shows the SEM image of fusion zone of LBW joint, which contains finer grains with more dense precipitates.
(1) Where S is the stress amplitude, N is the number of cycles to failure, n and A are empirical constants.
[13] ASTM International standard, E112–04, Standard Test Methods for Determining Average Grain Size, 2006, p.13

An additional challenge for the wheel vendor in these circumstances is to determine the minimum number of wheels required to confirm the validity of any given result.
This was also accompanied by a higher surface finish and a lower power with the tougher grains.
The A grain in the VSS bond gave 50% better life than the H grain at the same grade.
Department of Energy under contract number DE-AC05-00OR22725.
ABC Abrasives, Saint Gobain Ceramics, Boca Raton, FL, for the supply of CBN abrasive grain.

After deposition, reactions in the surface layer generated a number of secondary phases such as gels (NaCO3-rich or -poor), calcite, mirabilite, natron, and others.
The heap was composed of a number of layers of variable chemistry reflecting the slag type variation over the dumping history.
Thirty five solid samples were taken by core drilling over the whole depth range in regular depth intervals and analyzed for pH (10% w/v in water), total cell counts (acridine orange direct counts, AODC [5]), and numbers of cultivable, living heterotrophic bacteria (R2 agar [6] at pH 10).
Figure 2. a) Depth profile of Si, Fe, Ca; b) Na, K and S (calculated from SO3s) from solid (s) material in comparison to dissolved Na, K and S (calculated from SO4w) in water extracts in relation to c) stratigraphy (HP hardpan, GW groundwater level) and d) pH, total cell counts and numbers of living bacteria in the alkaline slag dump profile and underlying sand and GW; e) detailed view of the hardpan zone at the surface of the dump.
The flanks of the dump showed strong grain size variation and mineral sorting resulting in a very fine grained, highly agglutinated 100 µm thick top layer consisting almost entirely of gel produced from highly reactive glass with a porous coarse grained bottom layer.