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Most of the grains are white and in polygon shape, the grain boundary is straight, and a lot of twin grain is existed within the grain.
The average grain size is about 135 microns.
The other fatigue parameters are as follows, triangular waveform, the strain ratio is -1, the strain rate is 0.04%/s, The fatigue life (Nf ) is defined as the number of cycles for tensile stress to drop 25% from its peak value [9].
The fatigue crack of first-loop water environment initiated at PSB, impurities and grain boundary, which is same as that of air environment.
The grains separated into 2 parts after being traversed by the trans-granular crack, and grain orientations of the 2 parts changed a little for the first-loop water environment(Fig. 8b), while there are more for the air environment (Fig. 9b).

The transformation kinetics involved are complex and dependent on a number of variables, which is why many current numerical weld analyses use simplified approximations of the phenomena, or exclude these transformations entirely [6, 7].
Temperature (°C) zeq Temperature (°C) τLD 0 0 0 1 730 0 730 1 840 1 830 0.2 1000 1 900 0.05 1000 0.05 Austenite Grain Growth.
Some of the analyses using Equation (1) to capture SSPT’s assume a constant ASTM grain size.
The approach was found to be consistent for a wide range of ferritic steels, and assumed an initial grain diameter of 0.015 mm at 1000 °C [20].
The ASTM grain size number is then determined from the predicted diameter, and Equation (1) is updated.

Ultrafast cooling increased the density of dislocations and refined the grain size.
The higher cooling rate led to finer precipitates and provided greater number of nucleation sites for the precipitates.
The number obtained for the UFC process was 636, while for the ACC process was 488.
Thus, the UFC process not only increased the number density of the precipitates, but also refined the size of the precipitates. 4.
However, in the ACC progress, number of nuclei form and grow during the cooling stage because of the cooling rate was not very high.

It can be found that a considerable number of secondary phase existed at the grain boundaries.
When the solution come to 530℃ for 1 h (Fig. 3(d)), the numbers of residual phases did not decreased obviously but the grain size become larger.
With the increasing of solution temperature in the area 500℃~520℃, the number of T1 phase increased obviously.
The eutectic phases can be observed in the grain boundary.
When the solution come to 530℃ the numbers of residual phases did not decreased obviously but the grain size become larger.

MAC medium [4] adjusted to a pH of 1.8 either with ferrous iron (3 g/L), supplied as FeSO4 × 7H2O, or with pyrite grains (5 % w/v, 50 – 100 µm grain size) was used.
Pyrite grains (flotation pyrite, Baia Mare Romania) were wet-sieved for obtaining a fraction with a grain size of 50-100 µm.
Grains or coupons were washed and sterilized as described [5].
Viable Cell Number Quantification Using The Most Probable Number Method.
Koburger, Understanding and Teaching the Most Probable Number Technqiue, J.

Appropriate technologies may be adopted to reduce the number of passes of the microforming process as many as possible, which not only assist simplifies the manufacturing of tools but also simplify the handling system.
At the initial stage, the inhomogeneity of material due to miniaturizing was realised to attribute individual property to each grain by assuming that all the grains have a uniform Young’s modulus but individual tangent modulus
Pure copper was heat-treated to obtain various grain sizes.
The surface roughness of the rolled workpiece is relatively sensitive to grain size when the surface roughness of tool is 3.2 μm and it has significant increase when grain size decreases.
When surface roughness of tool is 0.8 or 1.6 μm, the effect of grain size on surface roughening of workpiece is not apparent and the surface roughness Ra only increases slightly with the decrease of grain size.

Phase depletion region at grain boundaries gradually widened.
It is worth noting that when the aging time was 500h, the holes appeared on the grain boundaries, and the holes numbers increased with the aging time.
The number corresponding to the diffraction peak is the d value of the phase.
In summary, it can be determined that the holes on the grain boundary in Fig. 1 were the α-Cr phase on the grain boundary in Fig. 5.
At 500h, α-Cr phase precipitates on grain boundaries, and the amount of α-Cr phase increases with aging time.

Material Preparation and Experimental Method Raw Material.Original grain size of Al2O3 (industrial powder 99a-Al2O3) is 2~3mm and slurry particle size is about 2.5 mm.
Specimen Preparation.To facilitate research, various samples were divided into five groups numbered with 0#~4# respectively.
Al2O3 andZrO2 are linked together closely and a large number of dimples exist that is why the mechanical characteristics of 3# ceramic specimen is better than the other sub-micron ceramics specimens.
In Figure (b), ZrO2 has an uneven distribution in Al2O3 matrix and a large number of gaps between them exist for the different of their linear contraction.
When ZrO2 content in sub-micron zirconia toughened alumina ceramics is 25%, Al2O3 and ZrO2 are linked together closely and a large number of dimples exist.

EBSD NordlysNano detector by Oxford Instruments with analysis system has been used to determine orientation of specific grains and analyze local texture.
It is of a certain value for each CSL boundary: ∆Θ = 15°/(Σn)1/2, where Σn is the number of coincidence sites under overlapping of three-dimensional crystal lattices.
Thus, the total number of α-phase orientations arising as a result of hot extrusion and cooling may be 8 × 12 or 8 × 24.
These factors may be the special boundaries Σ3 and Σ33a between the β-phase grains according to [22].
The boundaries may be substrates for the nuclei of new phase or a new grain [24].

Compression Perpendicular to the Grain.
The strength of the timber perpendicular to the grain can be seen in the Table 2.
In this instance, the utilisation ratio amounts to 185.91% and the structure fails to withstand the compression perpendicular to the grain.
Compression Perpendicular to the Grain with the Contribution of Reinforcement. 8 Screws were applied under the Sherpa connector in two columns.
Compaction - compressive grain [mm] Gap width - tensile grain [mm] Figure 9: Local deformations on all three samples Table 3: Local deformations on the test samples Sample number Compaction Gap width Difference [mm] [mm] [mm] 1 5.63 5.11 0.52 2 5.91 5.19 0.72 3 3.69 4.56 0.87 After disassembling the samples, no damage was detected on the total thread screws.