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Significantly deformed ultra-fine grained microstructure of the alloy was investigated by transmission electron microscopy.
The microhardness in the peripheral region increases with increasing number of HPT turns.
Grains are more refined in the peripheral part of the HPT sample due to higher induced strain.
Microhardness of Ti-15Mo alloy after various numbers of HPT turns represented by color-coded polar diagram Fig. 2.
· Microhardness of Ti-15Mo alloy increases with increasing number of HPT revolutions and also with increasing distance from the center of the sample

The maximum force offered by the particle on the grain boundary decreases with increasing lattice temperature and approaches the theoretical limit at high lattice temperatures.
Introduction Coarse, incoherent particles offer a drag to the motion of grain boundaries because of the interaction between the boundary and the particle.
Miodownik et al [3] used Potts model simulations and showed that the interaction between the particle and grain boundary is correctly captured only at lattice temperatures high enough to eliminate the faceting of the grain boundary when it interacts with the particle.
Therefore, the choice of the lattice temperature is far more critical in correctly capturing the interaction between an incoherent particle and a high-angle grain boundary.
The simulations were repeated with different seed values for the random number generator used in the Monte Carlo code, and the results shown represent an average of several runs.

Journal Title and Volume Number (to be inserted by the publisher) 3 The deformation of ferrite is thus shown to lead to the rearrangements of the dislocations in subgrain boundaries.
During deformation to a true strain of 0.7 at 750°C, ferrite appears at grain boundaries and within the grains of austenite (Fig. 8).
Some small equiaxed ferrite grains are also present near the austenite grain boundaries.
As shown in Fig. 12, after 30 seconds of isothermal holding, ferrite grains correspond to either elongated grains or equiaxed grains that are larger than the ones observed in Fig. 11.
Journal Title and Volume Number (to be inserted by the publisher) 5 In the case of intercritical rolling, beside deformed and extensively recovered ferrite, some equiaxed dislocation-free grains are induced by the deformation.

Several calculations were made preliminarily in order to estimate the sufficient number of layers.
Following these energy convergence calculations, it was estimated that 20 layers parallel to the grain boundary plane were required.
With the temperature, Al substitution in the grain boundary interface becomes stable.
Now if we compare for each impurity its formation energies within the bulk (Fig. 2) and at the grain boundary (Fig. 3), it is clear that both species have lower formation energies at the grain boundary.
Figures (a)(b) Figure 1: The figure a represents D03-Fe3Al crystal structure and the figure b represents a sigma5 (310) [001] grain boundary.

The tensile properties of both the as-cast DSC material and those thermally soaked for 500 hours at a number of temperatures were evaluated.
The number of alumina particles selected for consideration in the statistical analysis was about 400 in the SEM images.
Discussion This study has led to a number of new findings relating to the microstructure and mechanical behavior of Al-nanoscale Al2O3 particulate composites.
As the grains become larger, the driving force for grain growth becomes smaller and the pinning effect of the oxide particles becomes more important [37].
The large Al grain size is attributed to the casting method used to fabricate the Al-Al2O3 composite.

The multiphase metal behaves as a composite in which soft grains deform more than hard grains.
Pairs of adjacent grains are constituted by random selection in the total grain sampling.
Taylor FC ALAMEL FE-bricks FE-octo Number of time steps 20 20 30 30 CPU time 6 min. 7 min. 4 h 13 h Table 1 Comparison of the models with regard to CPU time (on a Pentium IV 1.7GHz).
In b.c.c. grains, slip systems are of the {110}<111> and {112}<111> type, whereas {111}<110> slip systems are active in f.c.c. grains.
In the present analysis, the grain size was uniform whereas f.c.c. grains are about 5 times smaller than b.c.c. grains in the real metal.

The elastic modulus is dependent on the fatigue load condition and the accumulated number of the load cycles.
The fitting constants are obtained, and the fitted equation is used to describe the degradation of Young’s modulus at N number of cycles.
However, the drawing process of the wires to 55% reduction of the area has resulted in finer grains in the cross-sectional area, while the longitudinal section displays elongated grains along the drawing direction with reduced pearlite interlamellar spacing (see Fig. 2 (c) and (d)).
Such grain refinement is due to the increased number of dislocations in the wire material during the drawing process.
The drawing process to 55% reduction resulted in finer grains in the cross-sectional area and elongated grains along the drawing direction in longitudinal section, which increased the strength of the wires.

Element Si could increase the number of nuclei, and then diminish crystal particles.
On the other hand, element Si could improve the casting performance of alloy, because it could reduce segregation of alloying element, thin grain boundaries, and reduce the number of dendrites.
The excess silicon segregating in grain boundary was detected by EDS analysis.
The increase of the second phase number in the grain boundary leaded to the serve pitting and promotes the self-corrosion of sacrificial anode.
The electrochemical properties were better when the anode has equable size and regular shape and suited-number second phase [12, 13].

During this process, strip temperature is of great importance for controlling metallurgical transformation and grain size.
Introduction In cold-rolling process, the grains of steel are flatten, internally distorted and hardened by strain.
As the heating temperature rises, the microstructure and mechanical properties of steel go through three stages of transformation, recovery, recrystallization and grain growth.
Numerical results In this paper, the grid number in width direction is set to 20.
The number of tracer point along the length direction of strip is set to 300, so the grid Fourier number is about 10-3~10-4, depending on strip speed.

The average number of flat grains on the surface (NA), the average surface of the grain cross-section (aav) and the average diameter of the flat grain (dav) were determined.
The β phase separated by grain boundaries occurs in the microstructure.
Zones in which the β phase occurs as thicker irregular grains, are seen.
Tin deposits uniformly within grains and preferably on grain boundaries and precipitates and non-metallic inclusions.
The grain growth is caused by the β phase tendency to decrease the surface energy of grain boundaries, which is the lower the larger are grains, since surfaces of their boundaries are then smaller.