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The nucleation activation energy Enucleation is greater than grain growth activation energy Egrowth, indicating that the nucleation process is harder than grain growth.
As a result, a large number of researchers have been attracted to investigate Cu-based amorphous alloys.
The glass transition activation energy Eg implies that metallic glass overcomes the barrier to restructure atomic configuration in the glass transition process; Besides, the onset crystallization activation energy Ex equals to the nucleation activation energy Enucleation and the final crystallization crystallization activation energy Ef is grain growth activation energy Egrowth [14].
The onset crystallization activation energy Ex is nucleation activation energy Enucleation and the final crystallization activation energy Ef equals to grain growth activation energy Egrowth.

The binary eutectic structure of α (Al) + Si is mainly distributed at the grain boundaries and the interior of grain is mainly α (Al).
The grain boundary structure is mainly binary eutectic structure of α(Al)+Si, which is similar to the microstructure of the cast aluminum alloy.
Variation in the ratcheting strain (%) with the number of cycles: (a-c) constant mean stress with varying stress amplitudes, and (d-f) constant stress amplitude with varying mean stresses.
The aluminum alloy is a polycrystalline alloy, and the orientation is mutually constrained by different crystal grains.

However according to the market value method, the loss estimation model can be presented by the following formula: In the formula: P’-grain market price, yuan/kilo; S1, S2-annual grain production respectively for clear water irrigation and sewage irrigation, kilo.
Losses of air pollution on agricultural are primarily reflected in loss caused by production decrease of grain, vegetables, citrus fruits and animal husbandry.
Land desertification loss mainly include grain production decrease loss caused by desertification and costs of managing desertification land.
Using market value method and recovery costs method, according to managing 1hm2 desertification land needs 60,000 yuan, the average grain loss by land desertification is about 20%.
The data comes from A, and the accounting formula is as follows: In the formula: P’-grain market price, yuan/kg; Q1-grain decrease amount by desertification, kg; S1-desertification land area, hm2 Vegetation resources destruction loss When choosing vegetation destruction dimension, space variant (area) is normally set as basic variant of ecological resource destruction[9], and can be estimated by market price method and recovery costs method.

Prior austenite grains were deformed by controlled rolling which refined the effective grain size [2].
And a large number of nano-size microalloy carbides precipitated in the matrix [4], as shown in Fig. 2d.
Some laths changed to massive ferrite grains or subgrains, and original high density dislocations changed to cellular substructures.
But a certain number of lath structure still existed, as shown in Fig. 2d and 2f.
The slight decrease of toughness after tempering at 600 °C was related to a large number of microalloy carbide precipitation.

Structure and microhardness In weld executed by TIG method with three beads, the flat crystallization front with staging grain boundaries melting are shown in Fig. 1 (a).
Small quantities of chrome carbides and eutectic niob under influence of thermal cycle in welds on borders of grains occurred.
The lower temperature of crystallization on grain boundaries caused solidification point flow in base material in fusion line Fig. 1 (c).
An increase in the pits and craters observed on the bottom of which carbides, nitrides and intermetallic phases were revealed by weak cohesive forces between them and the austenite grains (Fig. 5 d).
Nf - number of load cycles corresponding to the initial phase of a fatigue crack, R - coefficient of the cycle asymmetry, m - representative of the material (steel 1.4539 with TIG weld made ​​is 0.53, while for the laser connector 0.50).

Numerical simulated the segmented solid rocket motor’s working process, The influence of the internal flow field by the deformation of the grain especially the deformation of the inhibitor is analyzed.
The grain burning process is simulated by the user defined function of FLUENT which can add the energy, momentum and the mass to the chamber.
The structure zone consist of grains and inhibitors, the material property according to the Paper[8] does which is shown in table.1.The structural analysis code ABAQUS employs a finite element type CAX3H which including 13.7 thousands of meshes.
Because the number of flow field meshes is much larger than the structure, we just use the auto partition technology to partition the fluid meshes to three parts in FLUENT and use three processors to compute the flow field, the solid filed and coupled solution use the another one processor.
Since the protruding of the inhibitor, the Mach number is increasing around the downstream where indicate that the existence of the inhibitor will enhance the flow velocity at the downstream and influence the main flow.

Then, each of the specimens was tested for the fatigue life (cycle number-N).
Comparing the figures, as we can see in the first image, the surface has yielded serious plastic deformation (the black are the precipitates), and the shape of the grains have deformed and distorted seriously, the significant grains refinement could be found in the top surface layers (thickness is from 50μm), however, the refinement phenomenon become less obvious gradually and disappears at about the thickness of 300μm form the surface.
Due to the strain hardening and the fine grain strengthening of the UIP processing, the hardness of the weld nugget zone, heat affected zone and the thermomechanically affected zone has increased, especially the TMAZ.
The fatigue strength was increased from 75MPa to 114MPa when cyclic number was 2´106
(3) The UIP processing can generate plastic layer, refine grains, increase surface hardness, eliminate the possible existence of weaken area, and change the transverse residual tensile stress to compressive stress in the surface of welding joint ,which is the main reason for improving the fatigue property of Al 7075-T651 FSW joints.

For several years the major focus of material issues in SiC substrates was laid on the reduction of macroscopic defects like polytype inclusions, low angle grain boundaries and micropipes.
The shade of grey of the fields indicates the number of MPs inside the squares (white: zero, grey: 1-2, black: >2).
Low Angle Grain Boundaries (LAGB) Bright contrasts in stress birefringence images show disorders of the crystal lattice in the investigated substrates caused by stress, LAGBs or MPs.
In order to eliminate these nonusable areas we are continuously developing new seed generations with reduced low angle grain boundaries and MPs for our 3 inch production lines.
Continuously we work on next generation quality for 4H-substrates without micropipes or low angle grain boundaries.

It was likely grain in shape and the particle size in range of 2.94-4.06 µm.
A great number of materials with various morphologies have been reported including nanosheets and nanorods [5], polyhedral nanoparticles [6], core–shell structures [7], nanocages, and nanoframes [8].
However, to obtain the likely grain is because surfaces with high reactivity usually diminish rapidly during the crystal growth process as a result of the minimization of surface energy.
For CuO microparticle synthesized at higher temperature (200 ºC) for 4-6 h, Fig. 2 (c, d), the particle was likely grain in shape and the average particle size was 2.94-4.06 µm.
The morphology of CuO microparticle was likely grain in shape and the particle size in range of 2.94-4.06 µm.

This can occur by one of two mechanisms, one involving grain boundary penetration and the other grain boundary segregation [13].
In addition to the carbides, a number of intermetallic phases such as the sigma and chi phases form during long exposure in the temperature range 450-900˚C.
One important factor is grain size.
The complex alloy composition of DSS and their substantial ferrite content result in a tendency to form a number of undesirable intermetallic and other secondary phases in the temperature range 300-1000˚C.
The austenitic PH steels are therefore more difficult to weld than the other two types and require a number of measures that include high-purity base metal and filler metal and carefully selected welding procedures.