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The results are then passed up to a grain-level simulation where the response of a statistically significant particle ensemble is simulated via the evolution of particle distributions.
The growth of embrittling phases, particularly on the grain boundary, can also reduce the ductility of the material.
The instantaneous state of a material microstructure is assumed to be characterized by the mean grain size, the mean dislocation density and the number, size, location and composition of the different precipitate phases.
In this paper we restrict our consideration to the evolution of the precipitate phases, as little change in the grain size in IN617 is observed (due to the generous coating of carbides along the grain boundaries).
The subsequent decrease in particle number is due to coarsening.

The evolution of the microstructure from porous and columnar grains to densely packed grains is accompanied by changes in mechanical and physical properties.
Ion bombardment during vapour deposition of thin films, colled ion beam assisted deposition (IBAD), exerts a number of effects such as densification, changes in grain size, crystallographic orientation, morphology and topography of the films.
Therefore, in recent years, a number of measurements have been made in which nanoindentation and AFM have been combined.
Therefore, in recent years, a number of measurements have been made in which nanoindentation and AFM have been combined.
Indeed, there is a preferred growth of the biggest grains on the densest plane, in order to minimize the surface energy.

The wüstite grains in the grain growth stage have a columnar cell structure.
Our measurements indicate that the number fraction of high angle boundaries with rotation angle θ > 25 o decreased and the fraction of low angle boundaries with rotation angle θ ≤ 25 o increased during the continuous oxidation process.
In the LC steel sample , the ratio of the number of magnetite grains to the number of wüstite grains at the interface is less than in the pure Fe samples and the size of the magnetite grains is larger than in the pure Fe samples.
These grains have a wedge shape and are embedded within the magnetite grains.
Moreover, the hematite grains may span over two magnetite grains.

The added Sb2O3 did not dissolve in the ZnO grains but became segregated at grain boundaries.
Therefore, it is speculated that the increase in the FWHM of the spinel particles is due to an increase in the numbers of fine spinel particles at grain boundaries and triple points during annealing.
The following factors can be considered to be dependent on the thermal equilibrium temperature: (A) the amount of interstitial Zn 2+ between ZnO grains, (B) the crystal orientation of ZnO grains or the crystal structure of Bi2O3, and (C) formation of compounds such as spinel particles.
It has been reported that the electrical degradation characteristics of samples with Sb2O3 doping levels of 0.1 mol% or less is correlated to the orientation of ZnO grains since the mobility of oxide ions or Zn2+ ions depends on the grain orientation [4].
Thus, the α value correlates with the FWHM for spinel particles at grain boundaries.

As shown in Fig. 1 (a), the grains of MA alloy were relatively uniform.
After cold working, the grains of the alloy with a strain of 25% became longer along the tensile axis, as shown in Fig. 1 (b).
With increasing temperature of heat treatment for the cold drawn alloy, the grains became larger and uniform again.
Fig. 1 (c) shows the grains of the cold drawn alloy after heat treatment at 950℃ for 10minutes.
As shown in Table 2, specimen No. 2 had the largest number of surface cracks and the largest CGR.

One way to estimate the number of diffracting grains on the detector is from Poisson statistics, as demonstrated by [9].
If one assumes the grains in the gauge volume are Poisson-distributed, then one can estimate the actual number of reflecting grains NDG detected on the detector from Eq. 2, where u(I) is the actual standard deviation of the integrated intensity
The measurement results lie on the grain size statistics curve towards the left (with decreasing number of detected diffracting grains) and towards the right on whichever average fitting uncertainty (with increasing number of detected diffracting grains).
The advantage of having an automated primary slit system is that one can quickly find the best compromise to achieve having an optimal number of detected diffracting grains.
Number of detected grains on the detector versus the 2θ uncertainty.

In order to mimic polycrystals as realistically as possible, the well-known Voronoi’s polygon is adopted to generate grains with the mean grain size .
The anisotropy of grains is considered via given orientation of slip planes in each grain.
grain B grain A M O N GB l (a):Dislocation penetration grain B grain A M O N GB l (b): Dislocation emission Fig. 2.
In each grain, two slip systems are arranged.
Acknowledgements The financial support from the Program for Changjiang Scholars and Innovative Research Team (IRT 1027), NSFC under the Grant Number 11172188 and Fundamental Research Funds for the Central Universities is greatly appreciated.

However, their applicability is hindered due to the poor workability owing to the hexagonal close-packed (HCP) crystal structure and consequent limitations on the number of available slip systems [1].
Microstructure of the ZM21 alloy reveals single phase with an average grain size ~ 400µm and AZ91 alloy shows α-Mg and continuous b (Mg17Al12) precipitates along the grain boundary.
The recrystallized grain size is in the range 20-30µm.
However, the presence of β-phase in AZ91 may facilitate grain refinement by inducing large strain adjacent to the grain boundary and inhibit the growth of recrystallized grains.
At high temperatures, as in the present case, bulging of existing grain boundaries controlled by dislocation climb results in the formation of new DRX grains.

Lamellar grains of were observed in both materials.
The hardness evolution of NAH and PA materials with increasing number of ARB cycles is shown in Fig. 1.
This hypothesis was supported by TEM observations indicating that precipitate number density decreases with increasing number of ARB cycles [5].
In order to ascertain if pre-ageing affects the annealing response of the heavily deformed AlScZr alloy, a NAH specimen deformed by 6 ARB cycles was pre-treated at 300°C/2h to a 40 50 60 70 80 0 2 4 6 Number of ARB cycles Hardnes HV 10PA NAH 300°C/2h Fig. 1 Hardness evolution with increasing number of ARB cycles of both pre-treatment variants.
The AlScZr alloy has more than 5-times smaller grains.

The concrete piles reinforced with 500MPa fine-grain steel bars show good seismic performance and 500MPa fine-grain steel bars can be used in seismic design.
However, it still lacks of systemic research on the anti-seismic capability of column reinforced with the 500MPa fine-grain steel bars, which may cause inconvenience to define the design items and promote the application of the high strength steel bars. 500MPa fine-grain steel bars own high yield platform, and enable to reduce the number of steel bars appropriately, which is more economical and conducive to construction, can lessen incompact concrete which caused by too closed steel bars ,and then increase the durability of the concrete structures.
BF represents 500MPa fine-grain steel bars, B represents HRB335 steel bars and A represents HPB235 steel bars.
Conclusions Six concrete piles reinforced with 500MPa fine-grain steel bars under low cyclic reversed loading were texted and studied.
The concrete piles reinforced with 500MPa fine-grain steel bars Show good ductility and 500MPa fine-grain steel bars can be used in seismic design.