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However, VC particles are mainly used to refine grains other than becoming reinforcement. [1-4] V belong to transition metal In the periodic table, its carbide has high melting point, high hardness and high chemical stability, and VC has good compatibility with Fe ,so VC can be used as an ideal enhance body for steel base composite materials.
(a) 1050℃ (b) 1100℃ (c) 1150℃ Fig.1 XRD pattern of VC/Fe Composite metal material at different temperature Fig.2 SEM micrographs of fracture surface with different temperature, Contrast three fracture surface of fig.2, and from fig.2 (a) can find that particles fracture surface are piled together , and no fully combine with the matrix, defect and porosity, fracture mechanism is intercrystalline fracture along the grain boundary; VC particle in the fracture of Fig.2(b) is not obvious, and has certain consistency, the local area have tongue fractal stripe, so the fracture mechanism is combined intercrystalline fracture and dimple-crack, but the main fracture way was the intercrystalline fracture, and a small number of fracture was dimple-crack, proved that VC particles had fused with the matrix obviously, with less space; Fractography of Fig.2(c) changes from dimple pattern to mixed fracture with dimple and tear ridges, the pattern of local area was
(a) 1050℃ (b) 1100℃ (c) 1150℃ Fig.2 SEM micrographs of fracture surface with different temperature Surface morphology of Fig.3 (a) can clearly see that bar particles and lumps, contrast with the sinter's XRD pattern, it is that VC particles and Fe particles, the distribution of VC particles is strip along the grain boundaries and not fuse with iron fully, still exist a large number of defects and pore; Fig.3 (b) was better than (a), there are a lot of spherical VC particles and fused with Fe preferably, surface morphology is better, grain uniformity, but surface had a lot of pore; The boundary between spherical VC particles and Fe is not very obvious in Fig.3 (c), VC particles fuse greater degree with Fe, though there are gaps, but it is better than (b) obviously, the compactness has very big improvement, so shows good performance at this time.
The height of the peak gap is different with temperature increased; relatives to voids and grain size of abnormal grew up.
The process of recrystallization and grain growth reply will be occurred in the sintering process, the higher the sintering temperature, the greater the grain, the smaller the defect density of matrix, so the density increases, but the hardness drops.

It is commonly known, the significant number of atoms in nanoparticles are on the surface, and their contribution increases with decreasing of particle size.
Therefore the number of previously unpredicted thermodynamic consequences arise, in particular, the dependence of the melting temperature on the particle size.
To produce the concretes based on a three-component binder, the raw quartz sand was used as a fine-grained aggregate.
The type of dislocations will be determined by the trajectory of the quartz grain movement at the moment of impact with the blades of the mixer-activator: direct, tangential or tangential ones [5].
During the contact with water, the grains of tripoli almost instantly absorb it under the action of capillary forces.

The model includes a rectangular FCC single crystal work piece size of 50nm×10nm×15nm and a diamond cap grain of 10nm diameter.
During the grinding processes, constant press force is applied to the grain.
The central symmetry parameter is defined as follows: (1) where, (2) In Eq. 2, Ni is the coordination number of atom i, M is most popular coordination number and di, di+mi/2 are the vectors or bonds corresponding to a pair of opposite nearest neighbors in lattice.
Neighbor changing ratio During the grinding process, materials near on the work piece surface would have strong plastic deformation for heavy press by the grain.
As show in Figs, light blue atoms ( ci < 0.1) which is in front of the grain or around the grain are of dislocation or partial dislocation.

The roller matrix known from [15] allows to obtain the UFG structure with much less effort, but it requires a larger number of passes.
In this case, the deformation of the sample has a radial inhomogeneity, which can be minimized by a large number of revolutions.
Raab, Development of the Method of Equal-Channel Angular Pressing for Obtaining Ultrafine-Grained Materials: Thesis's Abstract ...
Raab, Development of methods of intensive plastic deformation for obtaining bulk ultrafine-grained materials, Bulletin of UGATU. 3 (2004) 67-86
Raab, Deformation methods for obtaining and processing ultrafine-grained and nanostructured materials, Gilem, Ufa, 2013

It is widely reported that dilatant shear bands are 'about ten grains thick' in granular materials and Figure 2: (a )A network of crystals (white) in contact at fs=0.36.
Figure 5b is a typical area of microstructure in the band region and shows that the pore band is a number of grains thick.
(d) EBSD map showing bimodal distribution of secondary grains and primary globules.
Instead, the bands are a number of in-cavity-solidified 'secondary grains' thick, suggesting that localisation occurred within a partially solid mixture containing a bimodal distribution of large primary globules and smaller 'secondary' crystals (Figure 6d).
A more detailed analysis is required to determine the role of each grain size population in strain localisation.

Introduction For a long time, in china, the forecast about insects in agricultural field is to use ultraviolet light to trap insects, after to reckon the number of insects by human.
The segmented image Assume all possible gray scales in image is L, n represents the image total pixels, is the pixel number whose gray scale is , to select a random number k as threshold at the beginning, is an array, the number of represents the pixel number of every gray scale in, is an array, the number of represents the pixel number of every gray scale in , Otsu method is to acquire a new threshold K which makes the variance to reach maximum, the Variance definition is(2)
Application of neural networks in the recognition of stored-grain pests[J].
Software Design of an Intelligent Detection System for Stored-grain Pests Based on Machine Vision[J].
[10] Qiu Daoyin,Zhang Hongtao,Chen Tiejun, Hardware Design of an Intelligent Detection System for Stored-grain Pests Based on Machine Vision[J].

In this work, Taguchi L9 orthogonal array with three variables and three stages has been used to reduce the number of experiments.
The S/N ratio was calculated by considering the Smaller the Better and Larger the Better Criterion provided by the equation (1) & (2): where Zij is different parameter and n is number of levels.
The weld has coarse grains over the nugget region which resist intergranular corrosion resulting in pitting corrosion as shown in Fig. 7.
The flat shoulder profile gives a finer compaction and heat to form a better grain structure to resist corrosion.
The microstructure analysis reveals coarse grain resist intergranular corrosion and left with pitting corrosion on the surface.

The average grain size is 50 μm.
Precipitates suppresses grain growth in V-alloyed steels during heat treatment and after quenching they have fine-grained structures with grain size about 10 μm.
For 1.5V-HNS, the number of dislocations in the pile-ups increases as the testing temperature decreases.
The austenitic matrix in 2.5V-HNS has some viscous fracture characteristics with a large number of dimples on the fracture surface and secondary cracks along the boundaries of austenite and coarse particles (Fig. 4f).
In V-alloyed steels, formation of a small fraction of brittle components on fracture surfaces occurs at the grain boundaries or in the grain body along the planar defects located between the particles.

The result shown that interphase precipitation of (Tix, Mo1-x)C arranged differently within the ferrite grains from near the grain boundaries.
The interphase precipitation in the ferrite grains had uniform inter-lamellar spacing, while the interphase precipitates near the grain boundary arranged inhomogeneous.
(a) 550°C, (b) 600°C, (c) 650°C, (d) the average grain size and standard deviations.
The phase transformation of austenite to ferite was completely finished and the grain size of ferrite was easy to grow at higher temperature, resulting in the larger ferrite grain (as shown in Fig. 2(c), 650°C).
The higher final rapid cooling temperature lead to a large number of precipitation in undercooled austenite, and reduced the supersaturated of the micro-alloying elements in the matrix before the phase transformation.

Cast ingots with optimized microstructure were reheated in various time and temperatures in semi-solid region to obtain kinetics of globularization and solid grain growth.
Introduction: The near net shaping process of thixoforming has a number of advantages over conventional casting routes, e.g., improvement of mechanical properties.
Coarsening kinetics can be described by the LSW theory with Eq. 1, [12]: D n-D0 n = Kt (1) Shape factor = απA Pa 4 2 (2) Deq = N A N N∑=1 /4 πα (3) Where Aα and Pα are area and perimeter of solid particles respectively and N is the number of particles.
In Fig. 6 grain size vs. reheating time for n = 3 was plotted.
This figure shows a good agreement between fit lines and experimental data which indicate Ostwal ripening mechanism of grain coarsening.