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It is suggested that the precipitation was took place in the grain on the dislocations and the stacking faults.
The specimen surfaces were mechanically ground with emery papers up to #1500 and polished with a diamond paste with a grain size of 0.1 mm [8].
Results and Discussions Fig. 1 shows the microstructure of alloys as-cast and solution-treated Co-Cr-Mo alloy representing a dendrite matrix with inter-dendritic and grain boundary precipitates.
Meanwhile, the relative number of transformed e-phase and untransformed g-phase were calculated by determining the relative intensities (I) of the g-phase and e-phase X-ray diffraction peaks.

In order to prevent laminate discontinuity, Liu [2] imposed a measure of material composition continuity and stacking sequence continuity between two adjacent panels, which is defined as the ratio of number of continuous plies to the total number of plies.
Inner and outer blending optimization models For inner and outer blending models, the design variables are the stacking sequence of the guide defined by a vector θ of ply angles and the number of plies to be kept for each panel ni, where i is the number of panels.
Master-slave parallel genetic algorithm Parallel genetic algorithm is adopted to decrease optimization time, which includes three types: master-slave parallel GA, coarse-grain GA and fine grain GA [7].
So for inner and outer blending models, the number of design variables is 50+6, where there are 50 variables for the fiber angles and 6 variables for 6 regions.
For generalized blending model, the number of design variables is 50+50, 50 variables for fiber angles and 50 variables for covered region numbers of plies.

If a small number of skychannels are used as division points, it can be regarded as coarse-grained region division, like Fig.2.
On the contrary if a large number of skychannels are used as division points, it is called fine-grained region division.
If the number of sc in free region then 2. 3.
Comparison Times and Channel Number.
Transmission Availability and Channel Number.

What is more, the application of the laser welding can obtain the excellent welded joints with small grain size because the very rapid heating and cooling can prevent the grain from coarsening.
The columnar that grew from the existing grain on the substrate retained the same crystallographic orientation. it is generally random for the grain orientation of the substrate, When the crystallization direction is roughly parallel to the heat flow vector through the solid-liquid interface can give priority to the development of columnar crystal.
Not only typical dendrite can generate on solidification front but also equiax crystal growth is favored at the center of weld due to the same condition around the internal grain[18-21].
Fig.2 (c) presents that the grains of HAZ has recrystallization and grain growth compared with the base metal, which can result in a dramatic decrease in hardness and strength.
The formula of “S-N curve” can be expressed as following: (2) (3) (4) where is equal to , is equal to, n is the number of the data points, a and b are constants, which can be determined through experiment.

It is known that the outstanding strength performance is attributable to the combined strengthening mechanisms of matrix and various grain boundaries.
This hydrogen usually trapped by vacancy, dislocation, grain boundary, precipitate, etc., can be released from each trap site by heating the steels.
steels, Laves phase existed predominantly along the prior austenite grain, as well as the carbides.
Takai et al. [7]reported that the hydrogen desorption profile formed in a relatively low temperature region reflects hydrogen released from not only dislocation but also vacancy and grain boundary, because the activation energies for detrapping from grain boundary and vacancy are very similar to that from dislocation [3].
Although the number of results is very limited and some scattering results can be seen, the CH2 is likely to decrease both with decreasing amount of solid-solution element and with increasing inter-particle spacing, namely, with the progress of precipitation and coarsening of M23C6 carbide and/or Laves phase.

Using ECAP process to the pure magnesium, AZ31 magnesium alloy, and ZK60 magnesium alloy results high-density defects and grain refinement and it has been already proved that ECAP method enhance the kinetic and activation energy performance of magnesium alloys [1].Furthermore, upon perform the ECAP process via longitudinal section for commercial AZ31 magnesium alloy showed grain size 1μm, and 4 wt. % of hydrogen absorption could be achieved within 15 hours.
It was observed that the grain size of AZ31 and AZ91 was refined after ECAP process (Fig. 1c, Fig.1f).
Increasing Al amount can provide additional grain boundaries, also increase the path for hydrogen diffusion that increase the hydrogen diffusion rate [11].
After ECAP process, the grain refinement can be observed which AZ31 grain refinement effect is better.
Addition of Al content in Mg based hydrogen storage material decrease the thermodynamic stability of hydride and increases the grain boundary that helps hydrogen diffusion.

As it can be seen in Fig. 3a, although the Al-Cu-Mg samples were subjected to the same total number of turns by HPT, the hardness depends on the HPT processing methods with the higher Hv values over the whole disk being observed for the m-HPT processed sample (16T).
In a qualitative sense the increase in hardness with increasing deformation during m-HPT is generally ascribed to the generation of dislocations, low angle grain boundaries and/or high angle boundaries.
On the one hand, this could be due to the reversal strain being so small that no grain boundaries generate, and after several cycles only a very low density of the GNDs will result and grain refinement will be limited.
On the other hand, the reversal strain is enough large to make GNDs accumulate and form grain boundaries which can be generally retained and strengthen alloys.
Vol. 55 (2007), p.933. ]: where d¢ is an L12 ordered phase, fully coherent with the Al matrix, and δ is the equilibrium AlLi phase, which forms mainly at grain boundaries [15].

Yeltsin», Ekaterinburg, Russia anikolai.nikulchenkov@urfu.ru, ba.a.redikultsev@urfu.ru, cm.l.lobanov@urfu.ru Keywords: Metal glass, solid-state amorphization, grain-oriented steel, non-ambient X-ray diffraction, structure simulation.
Also, Mg2Si appearance in solid solution leads to its amorphization instead of α→γ transformation Meanwhile, due to a large number of strong chemical bonds between elements, such a state is turned out stable enough both during subsequent heating and cooling.
The reported study was funded by RFBR, project number 20-08-00332 References [1] P.
Saikaly, Influence of initial heating during final high temperature annealing on the offset of primary and secondary recrystallization in Cu-bearing grain oriented electrical steels, AIP Adv. 8 (2018) 047605

The cutting action of the abrasive grain is replaced by the high-speed impact on the workpiece [5, 6].
Furthermore, the number of abrasive grains during the impact is counted so as to derive the final total grinding force formula.
The total grinding force is product of the single grit force and the number of the abrasive.
And the number of abrasive comes into grinding area also increases.
(2) The paper constructs the model for impact load and the number of abrasive in the impact area.

With the exploration and development of shale gas, the number of horizontal well has been increase sharply.
Meanwhile, there is a rapidly increase in the length of horizontal part and the number of fracturing segments.
The grain size is finer than ASTM grain size 13, banded structure lower than Grade 1.5 and inclusions lower than Grade 1.0.
The ultrafine-grained duplex microstructures lay the foundation for obtaining high-strength, high-plasticity and high fatigue resistance.
As the exploration and exploitation of deep oil and gas fields, such as Tarim Basin, Sichuan Basin and Junggar Basin, the number of extra-deep well is on the rise.