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The measured pull strength slightly decreased, as the number of cycles increased.
The Cu pad failure rate also decreased by increasing the number of thermal shocks.
With the increasing the number of thermal shock cycles, Sn grains were coarsened and it caused the decreasing pull strength of solder joint.
The total elongation of solder joint is decreased with increasing the number of thermal shocks and it was influenced by increased grain size.
Even though the IMC affects the fracture mode and the coarsened Sn grains change the initiation crack point, the pull strength did not change much even after 1000 cycles thermal shock treatment.

The grain size also was relatively large.
Compared with small size ingot (Φ93×300mm), the original grain and the skeletal shape phase on grain boundary of engineering ingot were bigger.
After homogenization treatment at 535˚C×30h, the skeletal shape phase were basically decomposed but at the grain boundary there was a large number of larger size second phase particles.
On the other hand, the slip of polycrystalline magnesium alloy was less that the grain was not easy to generate macroscopic yield and produce a lot of stress concentration at grain boundaries [6-8].
In addition to avoid grains grow up during heating after forging, we chose and multi-directional forging + directly extrusion deformation that was benefit for grain refinement and superposition of various deformation strengthening effect.

Crack initiation gains importance at larger number of cycles to failure.
For this purpose a TEM foil (Fig. 3a) was extracted from a surface grain where pronounced plasticity was observed after 107 cycles.
Newer investigations [10] showed by means of FIB prepared TEM-foils that first the grain refinement in the vicinity of the inclusions leads to a local decrease of the Kth as can be observed for fine grained materials.
It was shown that this process takes the largest fraction of the total life of the samples resulting in higher number of cycles to failure.
These results demonstrate that the number of cycles to failure is strongly correlated with the mechanism of FGA formation.

The grain size of the Cu films was evaluated as about 20-30 nm based on the X-Ray diffraction peak broadening.
From Fig. 1, one can see that the Cu film has the grain size around 30 nm or less.
After annealing of the films at 200 °C for 3 hrs, it was found that the grain size is somewhat increased.
In our previous investigation of the ultrathin Cu films, fatigue lifetimes of the Cu films with the same thicknesses defined by the number of cycles to damage Nd were determined using a method of the mechanical energy loss [10].
A high magnification of the crack has shown that the cracking was likely to occur along grain boundaries [11].

This is related to the increasing number of insulated buildings by ETICS.
The granular structure is characterized by a uniform grain size created by plenty of grains without grooving.
Figures 2 illustrates the grain size of 3.0 mm.
Grained plaster with a grain size 3 mm.
Grained plaster with a grain size 3 mm.

The pressure coefficient decreases for higher Reynolds number.
Their results illustrated the effect of porous medium thickness, Darcy number and Forchheimer number on heat transfer.
The porous medium is made of spherical grains.
The grains made of lead, which are non-magnetic, are 3 mm in diameter.
Influence of Reynolds number on Nusselt number of tube wall (frequency=3.91Hz, volume fraction =1.5 and mode3) The results of temperature distribution, convection heat transfer coefficient and the Nusselt number, under different Reynolds numbers are illustrated in Figs. 3 to 5.

The amount of MgO was 0, 1vol%, 3vol% and 5vol%, with the material numbers AC2NM0, AC2NM1, AC2NM3 and AC2NM5, respectively.
The decrease of fracture toughness is basically related to the small grain size of the grain boundary.
When MgO is added up to 5vol%, the microstructure reaches uniform and the grains are fine.
The grain size decreases gradually with the content of MgO.
The grain size decreased with the increase of MgO content and different phases were formed.

From Figure 1, we can clearly see grain structure of retaining ring materials, and find many slip-lines on grains.
Grain has begun to slip, but each slip-lines has different patterns, the distribution of slip-lines is not uniform; some slip has just begun, slip-line is on-and-off and there are rules inside the grain; while some slip bands of crystal grains have been very intensive, so that the color of grains is similar to darkly black, and some slip-line is thick, while others are thin, some slip-line of separation distance is larger, while others have less and intensive.
When boundaries of grain are damaged by deformation of retaining ring, dislocation inside crystal is blocked at grain boundaries, so stress focuses on grain boundaries.
When the concentrations of stress reach to grain boundary strength, grain boundaries will be extruded, and it generated crack.
Crystal grains around the crack exist a large number of irregular slip, with the characteristics of Hydrogen brittleness.

The grains on the plane of surface, where the layer is too thin, are small, but on the other regions were big.Fig2, Shows the AFM of transparent heat window (TiO2/Ag/TiO2/SiO2) thickness of silver layer is 225°A, and number of grains on the surface are more and coverage is complete.
Topography of surface indicates that the grains are ideal for this purpose.
The grains on the plane of surface, where the layer is too thin, are small, but on the other regions were big for TiO2/Ag/TiO2/SiO2 with 125°A silver layer.
AFM of transparent heat window (TiO2/Ag/TiO2/SiO2) thickness of silver layer is 225°A, and number of grains on the surface are more and coverage is complete.

For example, the sediment types can be divided not only by the grain-size, but also by the source, cause of formation, characteristic of sedimentary environment and substance content.
The designed principles of sediment symbols Symbols is the core of map information, and is one kind of signs that can reflect the number and quality of substance in the map.
Such as sediment types, physical and mechanical characteristic, acoustic, sediment grain-size and so on.
For example, we can classify the sediments to rock, gravel, sand, silt and clay based on the gradation of sediment grain-size when design the types symbols of types distribution map, and use the gridding-line, upright line, left diagonal, right diagonal and horizontal line as the basic symbols of each grain-size.
Then we can confirm the ranking as the grain-size of each group, for example, sand can be classified into coarse, medium and fine , distinguished by the size of space between lines.