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The main cracks always propagate along ferrite grains and follow the interface between ferrite grain and pearlite phase.
Many inclusions, pores, grains and grain boundaries will be excited to produce plastic deformation under low cyclic loading.
With the increasing of loading and the number of loading cycles, the number and volume of these points will grow.
The elastic and plastic deformation around the defects and grains will be the source of thermal dissipation under cyclic loading due to the material anisotropy [4].
Fig. 7c shows a set of infrared images of low carbon steel Q345 under the stress amplitude of 270MPa with crack propagation, the number under each image corresponds to the number of loading cycles.

Metallographic experimental results show that in welded metal with the increasing of weld heat input the quantity of bainite is decreased and crystalline grain is larger; but in both B610CF and 16MnR steel heat affected zone, with the increasing of weld heat input there is no distinct difference in microstructure.
But with the addition of alloying element mass fraction, the tensile strength can be higher by solution strengthening and fine-grain strengthening and precipitation strengthening [5].
But with the greater increasing of weld heat input the quantity of bainite is decreased greatly and crystalline grain size is become bigger, which can be caused that the impact toughness decreases in weld metal demonstrated in Table 4.
(a) 60μm (c) 60μm (b) 60μm (a) Y-1 (b) Y-2 (c) Y-3 Fig. 5 Metallographic microstructures in HAZ of 16MnR side In Figure 4, it can be seen that the metallographic microstructure in HAZ of B610CF side is ferrite and lathy bainite, on which slight carbide is dispersed forming into grain-shape and blocky-shape.
(1) In weld metal the quantity of bainite is decreased and crystalline grain size is become larger, and the impact toughness decreases

A large number of researchers have studied the precipitation kinetics of microalloying elements and their effect on microstructures [7-11].
The occurrence of recovery produces a decrease in the dislocation density which in turn reduces the stored energy (less driving force for recrystallization) and of the number of dislocation nodes, leading to a decrease of the available nucleation sites for precipitation.
On the other hand, no significant differences in the initial austenite grain size or in the values of the specific grain boundary area (SV), the latter calculated taking into account the particular deformation mode that operates in each case, have been identified between both types of test.
This could be enhanced in the present case due to the initial coarse austenite grain size.
There are few references about the effect of grain size on precipitation kinetics, but it is expected that all factors that influence the flow stress, as the grain size can, will affect the dislocation density and thus precipitation.

The results showed that there are the number of fragments of conduit whose most common shape is net-mesh and few whose type is spiral in this powder.
The shape of umbilic point of a starch grain was globular shape and V-shape.
The complex grains of starch which were consisted of 2 to 3 starch grain were found.
There are the number of fragments of conduit , the most of net-mesh conduits, and few whose type is spiral in this powder.
The complex grains of starch which consist of 2 to 3 starch grain are found.

Microstructure of conventional gravity cast CP-Sn specimen consists of relatively uniform large dendritic grains (Fig. 2a).
Size of the secondary dendritic grains are clearly finer than that of the control sample.
The slurry that exits the serpentine channel mold contains a large number of non-dendritic primary solid particles suspended in the remaining melt.
The general trend of decreased grain size with under-cooling can be described by Eq. (3), where D is the grain size, ΔT is the induced under-cooling and β and m (m <0) are constant coefficients [23].
Qi, Study progress and new trends of grain refinement in aluminum alloys, Non-Ferrous Mining and Metallurgy., 26 (2010) 32.

Due to the doping atoms are mainly in grain boundary segregation and litter of them will diffuse into the crystal, the resistivity of grain boundary increases more greatly with Cr, Mn and Co co-doped.
When the doping concentration of Cr, Mn and Co elements increases gradually, the doping elements are not homogeneous distribution in the grain boundary and grain, and the adding oxides produce heterogeneous segregation in the grain boundary, which leads to the result that the resistivity of part of the grain boundary areas increases greatly while the resistivity of other parts remains low.
Thus the current will pass through the grain boundary areas with low resistivity, which results in the nonlinear characteristics of ZnO decreasing.
The conductivity can be expressed as equation (3), where NA is the valence ion number
At the same time, doping with Cr, Mn and Co elements produces a large number of highly localized gap states in the ZnO band gap.

At ES = 15 J/cm2, the Ti concentration decreases from 36.4 to 2.4 wt% with increasing the number of pulses from 3 to 50 (Fig. 1b, curve 2).
After 75 and 100 pulses, the surface assumes a polycrystalline structure with a cellular substructure inside grains due to high-rate solidification.
The surface layer has a polycrystalline structure with grains of size 0.5÷7 µm and second phase particles of size 30–50 µn inside the grains.
The columnar structured layer passes into a polycrystalline heat-affected layer through a boundary layer formed by quasi-equiaxed Al grains of size 0.5÷1.7 µm (Fig. 5b).
The grain volume of the heat-affected layer also reveals second phase particles.

In order to research the effects of different microstructure on the mechanical properties for the as-hot rolled dual-phase steel, the steel was hot-rolled with different cooling rate (air cooling, 50℃/s, 90℃/s, 140℃/s, numbering of the samples was 1#,2#,3# ,4#) on the hot rolling mill in the State Key laboratory of Rolling and Automatic of Northeastern University.
When the grain size of the ferrite is a fixed variate, strength of the as-hot rolled dual-phase steel will increased with the increasing of the martensite volume fraction.
When the volume fraction is a fixed variate, grain size of ferrite become the main factor to the mechanical properties.
If the ferrite grain becomes finer, steel will get strengthened.
When the grain size of ferrite and the volume fraction of martensite increased at the same time, strength will increased also.

Preface Corn is an important grain crop in China.
The percent of damage and drop of grain and grain productivity are the key indicators to measure the harvesting performance of corn.
The proportion of average broken unit in whole number to present the percentage of damage of the grain was employed
Drop phenomenon happen to corn ear, we use the proportion of average drop unit in whole number to present the drop rate of the grain
(4) Harvesting energy consumption: only considered the work of grain harvest

In Fig. 2, in the two-step bias voltage experiments, number of ions moving toward to substrate target increases as the ring (auxiliary) voltage Vaa increases.
By the same token, the number of ions also increases as the negative substrate bias Vb increases as expected.
This implies that higher Vaa makes larger number of ion flux move to the target.
This implies that higher Vaa makes much larger number of ion flux move to target if the substrate negative bias Vb is higher.
In this two-step bias system, the number of ions moving toward to substrate increased as the ring anode bias Vaa or/and substrate bias Vb increased.