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The TTT diagram were drawn from metastable water quenched samples, therefore, these measurements were preceded by a solution treatment in the β field followed by water quenching, leading to a microstructure composed of single phased β grains with diameters ranging from 150 to 200 µm.
The as-received samples had been subjected to a large number of processing steps, including hot forging in β and α+β domains, resulting in a fully homogeneous material and a bimodal microstructure consisting of two phases α and β.
When titanium alloys are cooled from the β phase into the (α+β) phase, the grain boundary α phase (αGB) is formed.
From this αGB precipitation, α plates can grow into the β grain as parallel plates and are called αWGB (Widmanstätten Grain Boundary).

(a) Half of the crack length versus number of cycles (b) Crack growth rate versus for 300 MPa fitted by Nicholls model.
Among the effective parameters on the crack propagation hardness and microstructure characteristics did not support the observed increase in growth rate from NZ to TMAZ where the hardness decreased from 130 hardness Vicker scale (Hv1) in NZ to the lowest value of 118 Hv1 in TMAZ (see Fig. 1(b)) and the grains size in NZ (10 ) was less than the size of the elongated grains in TMAZ (50-100 ).
In addition the smaller size of grains within HAZ (50 ) compared with grains size in TMAZ accelerated the crack propagation.

An analytical method, for grain failure prediction under shock and vibration loads, was proposed by Besson [2].
Finite Element Method (FEM) was utilized for the calculation of the response of a SRM grain, during road transportation, due to random vibrations [4].
In the modal summation method only a limited number of normal modes, which have significant contribution in that direction, are required to be summed instead of all the modes in the vibration load range.
An example of shock and vibration design for a multi-tubular propellant grain, 18th Joint Propulsion Conference, Cleveland, AIAA-82-1101 [3] REN Ping et al.
[4] XU Xin-qi, The random vibration response analysis of the solid rocket engine grain during road transportation.

The interaction is not assumed to be a particular function of the Reynolds number, which is an advantage over traditional CFD-DEM couplings.
As explained in [2], within the DEM each grain of the soil is grepresented as an spherical particle.
Two grain sizes are used, 12970 particles have a radius of 0.4mm and 30 particles have 30mm.
This erosion process is clearly identified from this simulation as a distinct effect of the hydraulic gradient between these two different grain sizes.
The main question is why the small particles suffer increased buoyancy and are lifted into the void within the big grains and why the latest are sinking by gravity.

Ductile shear zone is consisting of numbers of subordinated shear zones; the rock within zones have a strong schistosity, cleavage and mylonitic [3].
Primary CO2-H2O inclusions mainly occur in lenticular and eyeball-like porphyroclastic quartz grains of stage I and II (Fig.2-b).
Fig.2 Characteristics of fluid inclusions in various quartz veins in the Saidu gold deposit: a-LCO2 inclusions in white quartz vein, SD2; b-LCO2-LH2O inclusions in white quartz vein, SD2; c-Primary inclusions (FI0) and secondary inclusions (FI2) in banded quartz veins, SD103A; d-Carbonic inclusions (FI0) within quartz grain and secondary inclusions (FI2) cutting quartz grains, SD103A; e-Carbonic fissures (C) occur along the stretching direction of eyeball-like quartz, while secondary inclusions (FI2) distribute vertical to eyeball-like quartz, 82-2-6; f-Secondary L-V inclusions (FI2) cutting the boundary of eyeball-like quartz, and cut by tiny fissures filling with sulfides (S), 82-2-8 Fluid evolution in structure-mineralizing stages.
Consequently, quartz grains are elongated to lenticular, eyeball-like quartz, some FI0 and FI1 inclusions have been destroyed, while secondary fluid inclusions FI2 were trapped in the direction of vertical or large angle skew with long axis of quartz. 3) in smoky gray quartz stage (in stage III), which is mainly characterized by forming of tiny fissures in quartz and filling of sulfides, late secondary aqueous inclusions were trapped in quartz of stages I and II, irregularly are formed.

Introduction The achievements in the technology of carbon materials allow us to offer a large number of techniques and methods for the synthesis of coatings, which, differing in structure and composition, can be used in solving various technical problems [1, 2].
According to [7, 8], the intensity ratio of D- and G-peaks is inversely proportional to the size of the sp2 clusters: ID/IG = c(λ)/La, (1) where ID and IG – intensities of the corresponding peaks; La – graphite grain size (nm); c(λ) – the coefficient of proportionality, depending on the wavelength of the exciting radiation (nm).
Statistical processing of AFM results Sample Annealing temperature [K] Average height, [nm] Rms, [nm] Average diameter grains, [nm] 1 - 1.1 0.3 78.0 773 5.2 0.8 45.0 873 1.9 0.4 46.0 973 7.6 0.6 43.0 2 - 1.2 0.6 65.0 773 2.4 1.0 64.0 873 2.3 0.9 96.0 973 3.1 1.0 66.0 3 - 5.0 0.6 44.0 773 2.4 1.4 112.0 873 4.0 1.8 140.0 973 3.7 2.3 166.0 The smallest roughness (Rms = 0.3 nm) is characterized by the coatings formed with a minimum power of ion-beam sputtering.
For example, for samples No.3, formed with the ion source power of 738 W, a linear increase in the roughness and size of individual structural formations (hereinafter referred to as grains) is observed, while for samples No.1 (432 W), the average grain diameter decreases, and the roughness and dispersion of the coating increases.

Meanwhile, during homogenization before hot working, complex metallurgical phenomenon happens such as element redistribution, phase dissolution, grain growth, defect migration, etc.
Through the combined observation OM and SEM/EDS, the light brown phase was able to be identified as Mg2Al3 which mainly located at grain boundaries.
Number in Fig. 3 Composition (wt.%) Al Mg Mn Cr Si Fe Ti Ca 1 95.50 04.50 - - - - - - 2 76.43 01.56 05.38 - - 16.64 - - 3 72.69 08.61 - - 12.50 - - - 4 92.42 07.58 - - - - - - 5 72.92 03.10 10.83 01.05 - 11.84 00.07 00.20 6 73.09 11.32 06.42 08.00 - - - 01.17 Fig. 4 shows the optical microstructures of AlMg4.5 and AlMg10 alloys homogenized at 420, 440, 500, 520℃ for 9h, respectively.
After the homogenization at all the temperatures of this study, the light brown Mg2Al3 phases at grain boundaries become dissolved into aluminum matrix with one exception of AlMg10 alloy homogenized at 420℃ for 9h showing small fraction of undissolved Mg2Al3 phase in Fig. 4(b).
With increasing homogenization temperature, the Mg2Al3 phase at grain boundaries are presumably more effectively dissolved.

Favourable characteristics of the material as low permeability, water absorption and overall very high homogeneity of the fine-grained mixture may, however, in some situations, present a serious risk.
For all examined variants was added to the fine-grained matrix scattered steel reinforcement both in the amount of 1.5%.
In parallel with the basic material properties has been investigated a number of other parameters, which will be presented in other publications [8].
Fine-grained mixture matrix was composed of the fine aggregate with a maximum grain size of 2 mm, cement, slag and silica fume.

The darker part close to black color in the grain boundary is pearlite which accounts for about 10% of the weight; while the lighter part close to a gray color is ferrite, accounting for 90%.
Yet, when being heated to 1000℃, the ferrite component, as shown in Figure 1 of the lightest color part close to gray in the grain boundary, remained at 90%, while the original pearlite composition, as shown in Figure 1 of the sheet-like feather indicated by the red arrow, completely disappeared and was converted into 5% bainite; and 5% of martensite was shown in Figure 1 as pointed by the red arrow.
At 1000℃, the composition of ferrite was reduced to 55%, as the lightest color close to gray in the grain boundary shown in Figure 3; 20% bainite, as the sheet-like feathers indicated by the red arrow shown in Figure 2, and 25% martensite, as indicated by the red arrow shown in Figure 2, were generated.
At 1000℃, the ferrite component was reduced to 20%, as the lightest color close to gray in the grain boundary shown in Figure 3; 35% bainite, as the sheet-like feathers indicated by the red arrow shown in Figure 3, and 45% martensite, as indicated by the red arrow shown in Figure 3, were generated.
Acknowledgement The authors wish to thank a kind subsidiary budget from the Ministry of Science and Technology (project number MOST103-2221-E-274-003-MY3).

Meanwhile, peak position appeared at 31.41° and 36.97° initially appeared as calcination temperature reached to 900-1000 oC, are plane of AlZnO (JCPDS card number 96-900-7020).
(1) Fig. 2 Variation of grain size of AZO nanoparticles Fig. 3 Micro-strain of AZO nanoparticles calcined at various temperatures.
Where D is the grain size, K is the shape factor, λ is the X-ray wavelength of CuKα, β is the full-width at half maximum (FWHM) and q is the Bragg angle.
Further increasing calcinations temperature from this range up to 1000 oC results to the drastic increase in grain size and high degree of agglomeration and the particles.
The grain size of the particles observed from SEM images is well agreeable to the calculated value from XRD results.