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In this study, to improve the productivity of A7075 alloy, the profile was cooled during extrusion to prevent recrystallization of extrudate surface grains due to processing heat and to prevent processing heat during forming.
These results indicate that cooling the extrudate during forming reduces the effect of heat generation during forming and prevents recrystallization of the extrudate surface grains and local melting of Zn.
The initial number of elements in the billet was set to 100,000.
The tearing is caused by the local melting of soluble intermetallic compounds containing Mg and Zn at grain boundaries due to the generated heat during extrusion, and the cracking propagates when strong tensile stress is applied to the extrudate during extrusion [4].
Consequently, the local melting of soluble intermetallic compounds containing Mg and Zn is inhibited at grain boundaries.

Based on this, the number of formed phases and the kinetics of their change depending on the cooling rate were determined.
As the rate of cooling the heat-affected-zone (HAZ) metal increases, the temperature of the start of phase transformations and the number of formed phases are noticeably deviated from equilibrium ones.
In all the variants (excluding the flat position), uphill welding was produced (Figure 1), as far as downhill welding resulted in a number of defects [32].
But in the grain itself, conversely, the Ni concentration decreases as the welding angle increases (Table 4).
This evidences the absence of phases containing Cr and leading to embrittlement of the grain boundaries.

Magnetic abrasive finishing (MAF) is a processing technology using magnetic abrasive grain (MAG) under magnetic field to finish surface of workpiece.
Grain Size.
The grain diameter of MAG includes the two parameters: D-The grain diameter of MAG, µm; d-The grain diameter of abrasive, µm.
The shape of MAG refers to the geometric shape of grain.
Supposed the intensity of magnetic induction is 1.2T, the lead diameter of excitation magnetic coins is 1mm, and its current is 1A, then the number of circles of each winding will be 1200.

For a given modulation period and modulation ratio, with the change of number of cycles the films can present a unique set of colours, and its electrical resistivity decreases with an increase in the number of cycles.
When the number of cycles is greater than 4, the sheet resistance is significantly reduced, and when the number is greater than 15, the prepared films come off.
It shows that resistivity decreases as the number of cycles increases.
When the number of cycles is greater than 4, the film resistivity is significantly reduced.
When the number of cycles is greater than 4, the sheet resistance is significantly reduced.

E=YH×10-5/∑Q×100% 2 Reduce the rate of soil erosion It refers to the number of the amount of soil erosion in the watershed management reduced.
Habitat Output Value (yuan / person) = output value / population 4 net per capita income It refers to the ratio of net income and number of population, in a certain period in watershed.
Per capita net income (yuan/person) = total revenue / population 5 per capita grain It refers to the ratio of total grain output and agricultural population in the watershed.
It reflects the level of per capita share of grain.
Per capita grain (kg / person) = total grain output / number of agricultural population 6 Hectares of food production potential to achieve rate It refers to the ratio of the existing food average hectare yield and potential ha yield, reflecting the level of food production potential of the mining.

Introduction Recently the severe plastic deformation (SPD) method becomes more and more popular among the researchers, as it allows obtaining bulk ultrafine-grained (UFG) materials with the average grain size of a few tens – hundreds of nanometers, which possess unique mechanical and physical properties [1-3].
The increase of the number of SPD rotations up to N=0.1 leads to a sharp decrease of the peak intensity (100).
N – is the number of rotations during the HPT.
The reorientation of crystallographic lattices of the grain structure occurs during the SPD by torsion at the initial stages of the process.
Such a tendency remains at further increase of the number of rotations up to N = 1 (Fig. 3е).

In principle, the etched metal thickness should be determined by the formed oxide thickness and the number of etching cycles.
The HPM-HCl DE shows to be linearly proportional to the etch cycle number [Fig. 5(c)], indicating that the formed oxide on TiN surface can be selectively removed by HCl.
In Figs. 6, AFM measurements confirmed that the DE up to 10 cycles does not induce obvious roughness to the TiN surface, indicating that the selected DE chemistries are less sensitive to the TiN grain sizes, grain boudaries as well as the crystal orientation.
The incoming TiN layer clearly shows grains with distributed grain sizes and boundaries as shown in Fig. 7(a).
Figure 8: The thickness and surface roughness of ALD HfO2 and TaN films as a function of HPM-HCl DE cycle number.

Mathematical Description of Grain Transformation The key problem of re-creation process model is grain transformation, such as form grain transformation, behavior grain transformation etc.
The grain space is transformed from fine-grain to coarse-grain.
So it can be used to deal with grain transformation and select appropriate grain by actual problems.
For example, suppose that there are basic behaviors , , , , ,a b c d e f and basic behavior spaces 1B , 2B , 3B , 4B .The domain of basic behavior spaces from 1B to 4B can be expressed as follows: 1 { , , , , , } X a b c d e f = , 2 {( , ),( , ),( , )} X a b c d e f = , 3{( , , , ),( , )} X a b c d e f = , 4 {( , , , , , )} X a b c d e f = From the above domain of different grain space, the number of elements in basic behavior space is reduced, and the grain of basic behavior space becomes thick, i.e. 12 3 4 ( ) ( ) ( ) ( ) B B B B ζ ζ ζ ζ < < < .
(2)Basic behavior space transformation is a process from coarse-grain to fine-grain.

Consequently, it is very difficult to suppress grain growth during sintering.
Keeping a fine grain size during the sintering of ceramics is a basic requirement to improve their mechanical properties, and it can be done by sintering at lower temperatures, in order to control grain growth.
A number of papers report the effect of a small amount of ceramic oxide seed particles on microstructure evolution during transformation of transition aluminas to α-alumina [3].
Many works [1-3] reported the addition of small quantities of MgO in aluminas in order to work as a sintering additive, suppressing grain growth and keeping small grain size.
It is very interesting, since the smaller the grain size, better mechanical properties will be attained.

Finally the samples were etched using 10% oxalic acid to reveal grain boundaries under the optical microscope.
The examination of the microstructures gives a grain size of 6-14 µm for BTM clinches and the grain size 10-15 µm for Eckold clinches as mentioned in the previous section.
These grain sizes are sufficiently small allowing a sufficient number of grains to diffract for the given radiated area.
In the vicinity of the clinch no grain deformation could be observed, which indicates that only the area close to the joint is affected by the joining process.
BTM Number of cycles: 0 1000 100000 Stress [Mpa] Error [Mpa] Stress [Mpa] Error [Mpa] Stress [Mpa] Error [Mpa] Die side-Q; X-direction 95.2 86.5 71.5 62.3 91.2 81.5 Die side-Q; Y-direction -202.7 53.4 -227.8 62.6 -152.6 42.2 Die side-L; X-direction -162.2 103.4 -72.9 74.6 -95.2 110.2 Die side-L; Y-direction 67.8 64 110.6 53.3 51.4 65.1 Eckold Die side-Q; X-direction 175.4 107.4 147.1 104.5 237.1 136.6 Die side-Q; Y-direction -21.5 85.5 62.1 96.7 62.7 72.2 Die side-L; X-direction -7.2 60.4 77.6 37.8 119.8 73.6 Die side-L; Y-direction 205 75.7 185.3 107.7 198.5 66.7 Conclusions.