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It was established that the particles of the hardener in the volume of the matrix are distributed evenly along the phase boundaries and in the body of the grains and reduce the number of pores formed during sintering compared with the original samples.
Grain boundaries are detected weakly in the α-phase and more clearly in the δ-phase, which indicates a high degree of coherence of adjacent grains.
Point micro-objects are present inside the grains, forming a dispersed substructure.
On samples with the addition of different contents of diamond powders, the number and size of pores are reduced or they are completely absent (Fig. 11).
With an increase in the number of particles of diamond powder above 3%, an increase in the carbon content in the material in the form of graphite occurs, and because of this, the filler particles do not completely oxidize, thereby increasing the number of pores in the material.

Due to the grain storage located in remote areas, the existing Monitor System for Grain is just monitored locally，and it is difficult to achieve remote monitoring.
Introduction Grain storage monitoring technology is one of the key technologies of scientific grain protection.
This system deploys a large number of wireless sensor nodes in the grain depot, which sample the grain temperature.
This system realizes remote temperature monitor of grain depot and data processing, and provides guarantees of scientific management of grain for administrators.
This system has been deployed in the actual grain depot, realizing the function of remote temperature monitor of grain depot.

The grain size in surface is smaller than the one in center.
The grain distribution is homogeneous in symmetric rolled specimen.
The grain of asymmetric rolled specimen is obviously different, the grain size in the specimen surface contacting with the roller (Fig 1.
In the distributed energy region, the number of nucleation site is large, then the precipitate particle size is small (Fig.3 (c) and Fig.3 (d)).
The precipitate particles nucleate and grow in grain of symmetric rolled specimen, and the precipitate particles tend to form in grain boundary in asymmetric rolled specimen.

It can be seen that refinement effect is increased with the rising of the pass number.
When the pass number is 12, the refinement effect of grains is not obvious, but the microstructure is homogenized.
Most of the grains size is about 6μm, some small grain can reach 2 ~ 3μm.
(2) The refinement effect is increase with the rising of extrusion ratio and the pass number.
When the pass number exceeds 8, greater pass number does not make grain refinement more obvious, but it makes the grain more homogeneous.

Its objective is to modify materials performance by designing and controlling grain boundary character distribution (GBCD) through a thermomechanical processing [1].
Grain boundaries with 1≤Σ≤29 were regarded as special coincidence site lattice (CSL) boundaries, and Brandon's criterion was applied to determine the Σ number for all boundaries.
Accompanying by the formation of high frequency low Σ CSL boundaries, the continuous random grain boundary network was extremely dispersed by introduction of low energy segments on migration random boundaries during twin emission and boundary-boundary reactions in the grain growth, see Fig.4.
Random grain boundaries and low ∑ GBs indicated by black line and gray line, respectively.
In fact, IGC propagates along GBs from the surface into the interior of materials and leads to mass-loss caused by grain dropping.

Qiu proposed the concept of coarse grain effect.
He believes in the process of fine particle flotation coarse grain to fine grained with a carrier, mediation and coagulation effect.
Powerful bubble washing way is beneficial to overcome the fine grained inclusion of gangue and nonselective reunion between mineral grains.
Microvesicles precipitation method is varied, such as in the pulp surface suction pulp caused negative pressure generated bubble, the electrolysis of water produced large numbers of micro bubble.
The research of fine grain carrier flotation hematite mechanism [J].

To achieve this, all processes employed commercially today seek to initiate solidification with as large as possible a number of grain "nuclei," thereby achieving a high "grain density".
In some cases a strong grain refiner is employed to obtain the high grain density.
If they are sufficiently large in number and hence small in size, they will ripen, on isothermal holding or slow cooling, into a structure suitable for semi-solid forming with little entrapped eutectic.
Figure 2 is a summary plot for Al-Cu alloys of roughly 4 to 7wt% Cu; data are from a number of investigators assembled by Bower, Brody and Flemings [3], from Bardes and Flemings [4], and from Annavarapu and Doherty [5].
Quantitative dendrite coarsening models have been developed by a number of investigators; these have generally involved simple geometries.

Microstructure observation indicates that Yb-α-sialon consists of equiaxial grains, but when increasing the radius of the doped cations, the elongated α-sialon grains form and the aspect ratio of grain increases slightly.
Some elongated α-sialon grains with grain core were found.
Surrounding the grain core, some misfit dislocations were seen.
In order to control the nucleation and obtain elongated α-sialon grains, some α-sialon seeds have been added into starting powers and effects of the size, morphology and number density of seeds have been studied [7].
Yb-α-sialon is entirely composed of equiaxed grains.

As can be seen from Figure 2A, the original microstructure of Ni30 superalloy is uniform, showing an equiaxial distribution, a small amount of particulate matter is distributed at grain boundaries and inside grains, and there are white bulk microstructure produced during casting on the surface of the microstructure, and a large number of plat-like annealed twin microstructure.
When the solution temperature is 1180℃, a large number of annealing twins appear throughout or along the grain boundary.
In the process of solution treatment, new phase nucleation produces a large number of layer faults, and then a large number of twins are formed [10].
Influence of solution temperature on grain size With the increase of solution temperature, the grain size of the alloy increases, the number of grain boundaries per unit area decreases, and the total interfacial energy decreases.
At the same time, a large number of γ 'precipitates are precipitated in the aging process, the fraction of γ' phase increases, and the alloy precipitation strengthening increases, which also avoids the abnormal grain growth at high temperature.

How a recovered dislocation structure gives rise to growing, strain-free grains has been debated for several decades.
Thus, a number of investigators have suggested that the strain-free nucleus must evolve from the recovered subgrain structure.
Journal Title and Volume Number (to be inserted by the publisher) 5 (a) (b) (c) Figure 2.
The probability of abnormal growth, Pabn, decreases as the critical angle θ* between low and high mobility boundaries increases (i.e. the number of high mobility boundaries decreases).
This model may be used to predict recrystallization nucleation frequency, as well as abnormal grain growth.