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With the assistance of ultrasound, grains are significant refined.
TiB2 particles exist on the α-Al grain boundary on trail and form clusters of large size.
The nucleation rate was increased, the wettability between matrix and particles was bettered and the grains were refined as well.
However, when the power was increased to a certain degree, for example, 2.0kW, the grain refinement was not obvious, but iron phase increased as ultrasonic amplitude transformer was corroded severely.
The force can be expressed by the following equation: F=2π2BωV03/[31+D3c2] (4) Where D=BkxMa; B is nonlinear coefficient of the transmitter, B=10; k is wave number; x is the distance from the sound source; Ma is Mach number; V0 is amplitude of the sound source.

We changed the number of the explosive, the number of the bottle, the bottle arrangement to examine the effect of shockwave on the "Cullet" size (fragment grain sizes).
Classified grain sizes were the following four grades; more than 4.75mm, 2mm～4.75mm, 1mm～2mm and less than 1mm.
From these figures, it is found that the weight distribution does not depend on the number of the glass bottle, but only depend on the distance from the explosive to the specimen.
glass bottle explosive shockwaves glass bottle explosive shockwaves after 30 µs (string type) after 70 µs (string type) after 30 µs (half of beer bottle) after 70 µs (half of beer bottle) (a) (b) glass bottle (a) (b) explosive Shock waves glass bottle Conclusions The results obtained are summarized as follows: 1) The weight ratio of the small "Cullet" grain sizes become high in the case of short distance between the bottle and the explosive. 2) The sphere type explosive can reduce the 'cullet' diameters more than string one. 3) The high-speed fracture process of glass bottle could be observed by optical methods. 4) The fracture process by underwater shockwave and underwater shockwave behaviors was simulated by LS-DYNA and the analytical results were good agreement with

Fracture delamination often found in the steel fracture test, leading to a large number of steel plates commuted or scrapped, seriously affect the rate of quality and delivery.
Results and discussion Scanning electron microscopy analysis revealed that the fracture sample hast a large number of large particles of MnS inclusions in it.
Expanding the equiaxed grain area can effectively reduce the dendritic segregation.
Adding nucleation agents, the use of electromagnetic stirring and diminishing the amount of secondary cooling water can be used in continuous casting process to reduce the columnar grain zone and increasing the equiaxed grain zone [6].
Conclusions (1)A large number of MnS inclusions exist in the fracture of 10CrNiCu steel, it increase the chance of cracks of the steel plate

When ZnO thin films was prepared at 500 OC, the crystallization of ZnO thin films was the best, and when the temperature was 450 OC, the grain size of thin films was the least, and internal stress was the least.
Texture coefficients can be shown as follow (Eq. 1): (1) In the formula: and are respectively represented diffraction peaks corresponding to crystal face of the prepared samples and ZnO standard samples (JCPDS 36-1451); is represented the number of peaks or crystal faces which are taken to calculate, three strong diffraction peaks of crystal face (100 ), (002), (101) were chosen here.
By the Scherrer equation , we could see the grain size of ZnO films first decreased and then increased.
Grain size of ZnO thin films at 450℃ is the least.
The crystallization of ZnO thin films prepared at 500℃ was the best At the substrate temperature of 450℃, grain size of ZnO thin films is the least, the internal stress of the films is the smallest

Wavy dislocation structures, similar to that shown in Fig. 1(a), are promoted in grains when a high number of slip planes are activated and dislocation cross slip is enabled [11, 14].
Only grains with a highly favorable (Type III grains) or unfavorable (Type I grains) orientation for twinning follow the Schmid behavior.
Small twins (few microns in length) nucleated at grain boundaries are commonly observed in these grains.
Type I and most of Type II grains.
Raabe, The effect of grain size and grain orientation on deformation twinning in a Fe–22 wt.% Mn–0.6 wt.% C TWIP steel, Mater.

The metastable cycle number is declined greatly with the increase of maximum shear strain.
Among these methods, equation of Manson-Coffin [1] which related to thermal cycle number and maximum strain is a typical one.
The results reveal that slow plastic deformation or grain rotation occurs inside the solder grains during the deformation processes, and is affected by their orientations and locations within the joint.
Fig. 3 shows the effects of maximum shear strain on the metastable cycle number and maximum shear stress of unit solder.
It can be seen that metastable cycle number is declined greatly with the increase of maximum shear strain from Fig. 3.

It can be observed that the structures, in all cases, are formed by polygonal grains of fine martensite (α') surrounded by Ti2Cu phase in grain boundaries.
The grain size is large, approximately 1500 µm, and very heterogeneous.
Grain boundaries are coarse and rich in Cu.
In the case of semisolid produced from previously deformed material, it can be observed in Fig.4(b1) to (c2) that resulting globules are significantly finer than the original eutectoid grains; also containing great number of intermetallic Ti2Cu precipitates.
Inside the globules Cu content is nearly flat and around 8wt%; this value increases close to the grain boundary: it can be observed a hallo of higher Cu content around grain boundaries limit.

The behaviour of the AlMgScZr is completely different : for both deformation modes, grain fragmentation is very limited and the initial grain boundaries are easily visible.
For AlMgScZr, no grain refinement occurs in either deformation mode.
It is important to note that at the end of each cycle (n x 3 x 0.2 where n denotes the number of cycles), the RCS is close to zero, which means that on each one of the 12 slip systems, the slip quantity produced during the first compression of a cycle ends up being annihilated during the two subsequent ones.
Fig 5.b shows the evolution of RCS for 4 randomly oriented grains strained by MF or uniaxial compression.
Since there is little grain fragmentation, the grain shape is directly dependent upon change in sample geometry.

Atomized powders of the alloy consisted of fine (<1 mm) aluminum grains separated by a grid of thin tin´s layers (Fig. 1).
In the case of alloy powders with finer aluminum grains the resultant structure has the greater area of interfaces, whereas in the case of powder mixture the large aluminum grains with a rounded shape are obtained.
Thus, the value of yield strength for the alloys with fine and coarse aluminum grains was about 40 MPa. 200µm a 100μm b Fig. 3.
It is seen that the strength of alloys changes linearly with increasing number of passes of more then one.
Improvements of the wear resistance are observed after first two pressings, and it practically do not change with further increase in number of passes.

In the as-cast conditions the Mg–6Al–2Sr alloy consisted of α-Mg grains with intermetallic phases: (Al,Mg)4Sr, Al8Mn5 and Al3Mg13Sr.
After die casting, a considerable reduction of the solid-solution grain size was found.
Similarly to the solid-solution grain, the intermetallic phase precipitates are much smaller compared to those of inan ingot.
It is related to lower number of Al3Mg13Sr phase precipitates.
Globular precipitates of Mn5Al8 phase appear both on the boundary as well as within α-Mg solid solution grains.