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As a result, the production of massive ultrafine-grained Zn-Al products process became possible and high strain rate superplasticity at room temperature due to ultrafine-grained microstructure could be revealed .
In Fig.2 with low magnification, α-grains with the size of about 1 μm (Al-rich particles) and β-grains (Zn-rich particles) exist together.
Fig.3 with high magnification shows β-grains, the size of which was verified to be about 30 nm.
Fig. 2 FE-SEM image of asrolled Zn-Al alloy Fig. 3 FE-SEM image of as-rolled ZnAl alloy focused on β-particles εtotal = (4n - 3)ε (1) where n is the number of accumulation, andε is the strain amplitude (±0.1 %).
(1) By applying TMCP to Zn-Al alloy, a massive ultrafine-grained material was manufactured successfully.

Main factors influencing the mechanical, corrosion and aesthetical properties of the product, as well as the ease of extrusion, are the grain size and the presence and distribution of intermetallic compounds.
In order to deal with the great number of material and process parameters involved in this correlation, careful planning of the testing procedure has to be considered, inasmuch as it affects the range of achievable strains and strain rates, the repeatability of the results and the accuracy of the measurements.
The microstructure consisted of coarse aluminium grains (average size about 90 µm), with large aligned constituent particles at the grain boundaries.
EDS analyses indicate that these particles were mainly iron-bearing intermetallics: AlFeSi and AlFeMnSi (Fig.3 c-d); while some coarse Mg2Si particles were observed at the interior of the grains.
On the contrary, the minimum effect on grain size and morphology was shown on zones closer to the die, characterized by less deformed grains (Fig.4-b-III).

Schematic illustration for the phase separation composed of FM-grains and COI phase.
(b) If the FM-grains are disconnected by grain shrinking, the percolation paths are broken, corresponding to the LR and HR depending on extent of disconnection.
It is expected that the size of FM-grain is shrunk with elevating the local temperature in the sample by the current, then the grain connection is disconnected as illustrated in Fig. 8.
A very simple explanation is that the FM nature in FM-grain is enhanced by the photo-hole doping, resulting in the size expansion of FM-grain and enhanced connection.
Small numbers of the FM-grains (metallic state) in LBMO layer are contacting to ZnO layer, forming metallic contact.

Introduction Wood is main structural form of ancient architecture in our country where have a large number of existing timberwork residence, such as temples, ancient building floor tower, pavilion etc. with distinctive features, on the one hand, wood has advantages of high quality lighter, arrange grain strength, on the other hand, it also has low horizontal grain strength, more wood section crack, creep, modulus of elasticity is small, easy to affected by dry-wet circulation decay, such as faults.
The second group pasted CFRP cloth at the bottom of the wooden beams across all along the grain layer, B1 and B2.
The third group pasted CFRP cloth at the bottom of the wooden beams across all along the lines two layer Numbers of C1 ~ C2.
The fourth group pasted all three layers of CFRP cloth at the bottom of the wooden beams across arrange grain, no.
The ultimate load of the beam also increased with the increasing of the layer number of CFRP cloth.

And the grain boundaries become clearer.
And there are a number of precipitates in the impact fracture (Fig. 2 (b)).
There are a large number of dislocations and twins in the martensite.
And in the same grain the orientations between the martensite laths are different.
When the crack propagates in the distorted grain, the contiguous grain boundaries are heavily deformed and connected by tearing.

By virtue of these properties, beryllium bronzes have a wide number of applications, including as spring materials.
Subsequent aging (refer with Fig. 1b) led to the precipitation of the phase along the grain boundaries.
The mixture of the matrix and precipitation phases expanded from the border to inside the grain [4, 5].
The number of the bending-and-unbending test remains at the high level of more than 200 units.
However, the number of bending-and-unbending tests, an important characteristic of toughness for spring materials, remains at a high level.

(1) where Γ is the Gibbs-Thomson coefficient, R is the dendrite tip radius, Pei is the Peclet number for i, mi is the liquidus slope, C0,i is the initial concentration for i, ki is the partition coefficient for i, ζc(Pei) is a function of the Peclet number, Iv(Pei) is the Ivantsov solution and Ghkl is the average temperature gradient near the dendrite tip.
This welding configuration is deficiency of centerline grain boundary formation.
Meanwhile, coarse dendrite size, plentiful solute enrichment, wide solidification temperature range and severe stray grain formation are simultaneously satisfied.
Numerical analysis of microstructure development during laser welding nickel- based single-crystal superalloy part I: stray grain formation.
Precipitates in coarse-grained heat-affected zone of Ni- based 718 superalloy produced by tungsten inert gas welding.

Screening and hydrometer combined test is used for determining the grain composition of Ginger-stone soil.
The sample is produced through heavy compaction test, with the number of pounding 30, 50 and 98, and CBR experiment is conducted after 4 days and 4 nights of water saturation.
The CBR value obviously increases with the increase of the pounding number under the same material ratio.
When the Jiang-stone content is in the range of 30% to 50%, its compaction characteristic belongs to a transitional state between fine-grained soil and coarse-grained soil, and can be compacted using low-frequency and strong-vibration.
When content is more than 50%, it belongs to the coarse-grained soil, and can be compacted using high-frequency and strong-vibration.

Originally, ECAP has been developed for the fabrication of ultra fine grained alloys.
The density increases with number of passes for alloy and composite.
The hardness increases due to the dispersion and grain refinement during milling and sintering.
The composite shows higher hardness than the alloy with increase in number of passes.
The better density and hardness are obtained with increase in number of passes.

For example, as long as the volume fraction of grains is far from the maximum packing density of grain particles, the material can usually be considered as a paste like material; otherwise in the presence of a greater amount of particles, the behavior is dominated by the granular nature of the material.
By considering a spherical shape for the grains and a constant thickness for the excess paste, the specific volume of the granular skeleton (Vs) and the excess paste thickness (δp,e) can be calculated by Eq. 2 and Eq. 3 where ri and ni represent the radius of particles of fraction i and the number of particles per fraction i, respectively.
N1 N2 N3 N4 N5 N6 Glenium 51, [%] 0.56 0.64 0.71 0.87 0.98 1.26 Characteristic stress (Cs), [Pa] 57 48 37 29 22 11 Table 2: Mix proportions for one liter sample Mix type Void paste fraction [%] Excess paste fraction [%] Thickness of paste layer [μm] Number of grains in granular skeleton LP3-B 26 27 180 8.9 E+04 LP3-C 22 38 270 7.5 E+04 LP3-D 18 50 390 6.1 E+04 Experiments In order to study the effect of property and proportion of the pasty phase on consistency, 18 different mixtures were prepared and tested by the mini slump cone (JIS R 5201:1997).
Based on this method, a material is considered as an assembly of a finite number of individual elements and the macroscopic behavior of material is related to interactions between material elements by an associating repetitive application of the law of motion to each element, and a force-displacement law to each contact [7, 8].
In this research, in order to study the effect of the excess paste characteristic (consistency and thickness), two phase elements are applied as a fundamental elements that consists of an inner core of an aggregate grain covered by a layer of paste.