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At grain boundaries (GB) and within the grain M23C6 carbides were identified.
The TEM investigations were performed within the grain and at grain boundaries, Fig.6.
Size and number of particles of precipitates of both states are almost the same.
After thermal aging, γ’ precipitates are larger and the number of particles decreases.
A reduced number of γ’ particles at a size of 55 nm and a coarsening of M23C6 at GB and within the grain was observed in thermal aged condition, where besides some Ti-rich MC (TiC) as in the initial state and also some η phase particles were observed.

Further increase the deformation temperature to 500°C (Figure 4c), recrystallization occurs in some deformed grains, especially a small amount of recrystallized small grains at the triangular grain boundaries.
When the amount of strain is 0.5 (Figure 5a), the aspect ratio of the alloy grains relative to the equiaxed grains increases.
When the strain increases to 0.8 (Figure 5b), the aspect ratio of the alloy grains further increases, the grain boundaries of the partially deformed grains expand, and dynamic recrystallization starts.
Further increase the strain to 1.2 (Figure 5c), the deformed structure of the alloy is fibrous, and fine recrystallized grains appear inside the deformed grains or at the grain boundaries, mostly at the original grain boundaries.
The deformed structure can undergo a large amount of dynamic recovery and dynamic recrystallization, the substructure structure grows, and the dynamic recrystallization crystal A large number of grains are distributed along the grain boundaries of deformed grains.

Based on the grain size distribution analysis and plastic index, the soil is named as silty clay.
The numbers of cycle, n, are 0, 1, 4, 7, 10.
Fig. 5 Cohesion versus freezing-thawing cycle number.
Fig. 6 Inernal friction angle versus freezing-thawing cycle number.
Liu, Experimental study of the shear strength characteristics of fine grained soil under freezing and thawing cycles, J.

Grading determines the name of the conglomerates and characterizes the distribution of grain by their size [1].
With the inbuilt- function we can count (calculate) the number of grains in the sample of coal charge with a threefold increase in the scheme (refer with: Fig. 1).
Fig. 1 The scheme of the experiment The experiment of the percentage estimation of grains in the sample of coal charge is following.
The equation of the size distribution of the grains relative to their number is the next: , where is the square of i-grain, pixel; N – a number of grains; – conversion factor, m∙10-6/pixel; a – width of the frame, m∙10-6; n – the number of pixels in the column.
b) If x/y > 2/3, then , where – volume i-pore, mm3; R – circle radius, mm, N – number of circles, entered into pore.

They are featured by uniform distributed particles and needles at the vicinity of grain boundaries of primary ferrite.
Shear deformation is a common feature during ECAP process, which leads to the formation of kinks on grain boundaries 10.
Fig. 3(c) shows large number of microtwin are retained in austenite after four passes, which demonstrate the deformation twin is the main grain refine mechanism for austenite.
Fig. 3(d) demonstrates one shear band in ferrite, in which some equiaxed grains were formed.
Deformed structure shows the deformed twin induced by shear stress is the main grains refine mechanism in austenite, whereas dislocation activities result in grain subdivision in ferrite.

The appearance of the shoulder peak can be attributed to the presence of the small grain at 80oC or so.
In the process of degassing treatment, acetophenone as crystal nucleus makes material to grow into a large number of small grains at the optimum temperature, and these small grains gradually grow perfect with increasing the time of degassing process.
It can be seen that, the grain size of the outer samples is significantly smaller, grain sizes of the middle and the inner samples are bigger and more uniform.
The outer samples’ grain size increased obviously, and the incomplete grains grow to perfect after the degassing process.
Non-volatilized by-products played as crystal nucleus to form new small grains, and these grains made shoulder peaks appeared in DSC curves.

Table 1 Compositions of nano-micro composite self-lubricating ceramic tool materials Sample Number Material Content/vol.% VMicro-Al2O3 VNano-Al2O3 VTiC VCaF2 VMgO 1 40 0 49.5 10 0.5 2 36 4 49.5 10 0.5 3 20 20 49.5 10 0.5 4 0 40 49.5 10 0.5 Results and Discussion Mechanical property.
Second, the nanometer Al2O3 can improve the size of crystal grains.
It can be seen that the grain size decreases with the increase of nano-Al2O3.
The large grains with grain size of about 5 μm (Fig.3 (a)), and the mean grain size is about 2 μm (Fig.3(b, c and d), which confirmed that the addition of nano-Al2O3 could restrain the abnormal growth.
There are two kinds of nanoparticles, the smaller nanoparticles can be found in the matrix grains and the bigger nanoparticles on grain boundary (Fig.3 (b)).

The design of grain boundary and its stress is important for their bonding states.
But except for numbered systems, such as Co/WC and Ni/TiN, few systems have reached the people's expectation mainly for the poor wettability between metal and ceramic.
SiC-AlN solid solutions, mainly existing at the grain boundary of SiC, prevent the grain growth of SiC particles and improve the boundary movement and diffusion therefore lowered the sintering temperature [13].
Figure5 shows the different microstructures of Co/ Al2O3 system by grain boundary design [14-15].
The amorphous layer will impede the grain growth and keep the fine grain size, which strongly affect mechanical and magnetic properties of the composites.The improvements in bending strength (from 568.3 to 676.1MPa) and fracture toughness (from 5.16 to 6.28MPa.m1/2) were achieved compared to the Co/Al2O3 system.

Rate of crack propagation is determined by space and size of grain boundaries precipitates and size and distribution of intermetallic particles around grain boundaries.
The grain boundaries microstructure of aluminum 7075 T6 alloy marked with extremely fine-sized MgZn2 precipitates distributed evenly along grain boundaries [11] and intermetallic particles spread randomly around grain boundaries.
Rolling resulted in formation of dislocation networks, both inside grain and grain boundaries, with dislocation density increased with increasing %-reduction.
In addition to producing dislocation networks in grains and grain boundaries, rolling also tends to break intermetallic particles into small fragments and scatters along grain boundaries.
Addition of further retrogression time will cause over-aging, which decreases number of solute inside alloy and decreases next aging effectiveness.

According to the principle of grain storage, the ventilation and cooling should be adopted rapidly and efficiently when the new grain come into the granary, which can avoid the dew condensation between the new grain with high temperature and the granary wall with low temperature.
The granary is round, and its bottom is cone in order to discharge grain easily.
The number of all meshes is about 400 thousand.
While after 6h, whole grain bulk has already cooled in project A, and half of the grain bulk has the similar temperature as the flow air.
The cooling of the grain far from the mesh pipe is not obvious.