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During single electron beam irradiation to 3.6dpa the dislocation loops with lower number density were formed near the grain boundary.
At 3.6dpa the loops with higher number density were formed.
The smaller size void appeared with higher number density at 8dpa.
Fig.3 shows the dose dependence of void size and void number density.
Fig.2 Void structure observed in Fe-Cr-Mn(W、V) alloy irradiation at 673K to 10dpa Fig.3 Dose dependence of average size and the number density of void in Fe-Cr-Mn(W、V) alloy Irradiation-induced solute distribution near grain boundary.

However, there are few reports [12] concerning about the fatigue property of ultrafine-grained steel.
Fig.5 shows relationship between the load ratio of (applied stress)/(tensile strength) on fatigue tests and number of cycles.
It is found that the stronger filamentary microstructures of the ferrite phase and the pearlite phase are developed with increasing number of passes of the pure shear deformation.
From the results of TEM observation, the ferrite phase with a grain size of 1µm is observed in the microstructure of all carbon steels after heat treatment and the grain size becomes larger with decreasing Vickers hardness.
A grain size of the ferrite of the pearlite phase is sub-micrometer due to the presence of the ultrafine spherulitic cementite.

The increasing versatility of testing machines, like dilatometry with easily variable temperatures, in addition to the growing expenses that go along with increasing the number of experiments for high cost materials, leads to the question whether performing all those experiments is really justified.
Reducing the number of experiments by 50 % during materials characterization therefore appears feasible.
The grain sizes after cooling are measured metallographically.
Similar spacing is used for the matrices covering grain growth, srx kinetics, grain size after drx and srx respectively.
While in classical models grain growth can only start after full srx, Fig. 8 shows that grain growth starts while srx is still in progress.

The study has revealed three structure types in the alloy: (1) a smooth shagreen-type structure (an orange peel), which turns into a stripe-like structure (2) in some areas, and a grain structure (3) to appear as lengthy thin layers with the width of 50-80 µm and an average grain size of 12.5 µm, the most probable size of grains is detected to be in the range from 10 to 15 µm, a preferred number of such grains is 31%.
It is noteworthy that an increased number of micropores are detected on the boundary between these types of structure.
There is a grain structure in several areas in the form of lengthy thin layers with the thickness varying from 50 to 80 µm and average grain size of 12.5 µm (Fig. 1 d).
The grain size distribution demonstrates the most probable dimension of grain to range from 10 to 15 µm.
An average grain size in the identified structure was determined to be 12.5 µm, the most probable size of grains ranges from 10 to 15 µm; that is 31% of all grains.

The latter explanation predicts that new grains should begin at low angles to old grains.
A histogram of misorientation versus number of boundaries shows a gap at 15-20º.
The larger grains are interpreted as the relict cores of original polygonal grains.
The smaller and/or very irregular grains have formed by recrystallisation from these "parent" grains.
However, grain boundary migration does not itself change the orientation of a growing grain.

The grain size distributions after the tests are plotted in Fig. 1.
For the ultimate grain size distribution, D is always around 2.5 [6-10].
Therefore, in this condition, the Bpi is defined as the area between initial grain size distribution and ultimate grain size distribution up to 0.5 mm particle size and the Bt is defined as the area between initial grain size distribution and current grain size distribution up to 0.5 mm particle size, as shown in Fig. 3.
The conclusion further verifies that the number of broken particles increases with the increasing confining pressure during compression.
The number of the largest particles decreases with the increase in confining pressures, and the number of smaller particles increases with the increase in confining pressures.

Ti inoculation level was changed up to 0.1wt% by adding Al-10Ti master alloy into 3003 aluminum melt as grain refiner.
A number of components are press-formed at room temperature and then assembled to a net shape.
An Al-10Ti master alloy was used for grain refining of 3003 alloy, and the consequent effect of grain refinement on strength and formability of the clad aluminum sheet was examined through tensile tension test and hemispherical dome stretch test.
Grain refinement significantly increased the biaxial formability of the 4343/3003/4343 clad sheets by 2 times or more.
It appears that an isotropic and fine grain structure was more favorable to biaxial formability.

The as-cast ingots were cold-rolled into sheets 1 mm thick, which were annealed for 1.8 ks at 350℃, resulting in a fully recrystallized grain structure with a mean grain size of 41 µm.
boundaries, while the elongated grains are often subdivided by low-angle boundaries.
This map shows the presence of a number of boundaries with misorientation angles less than 2°, which further subdivide the grains into smaller units.
The dislocation density is, in general, higher in the elongated grains than in the equiaxed grains, as can be seen in Fig. 2(a).
Micrographs taken under such conditions were used for dislocation density measurements and it was found that the density within the equiaxed grains is 1.0 ×1013 m -2 and 3.5×1013 m -2 in the elongated grains.

These materials can be produced through a number of chemical and physical processing routes, the best results, so far, have mainly been attained by Severe Plastic Deformation (SPD) processes.
The grain size distributions and the average grain size were obtained after measuring individually more than 250 grains in each case.
The grains were equiaxial with a homogeneous grain size distribution [7].
Especially in the 0.55 %C milled powder, a great number of carbon atoms are present in the ferrite grain boundaries and also interstitially solved in the ferrite, occupying the dislocation cores [11,12].
In this case, the absence of carbon leads to the rapid growth of some grains and a little number of grains are clearly larger than 1 µm.

Electropolished specimens were also examined by scanning electron microscopy using atomic number and channelling contrast in the back-scattered electron mode.
Grains in the core alloy are distinguishable by virtue of channelling contrast while the Mn-rich dispersoids appear much brighter because of their higher average atomic number and the solidified eutectic shows as a fine network of silicon flakes.
Grain growth has taken place where grain boundaries were replaced by liquid films.
Examination of a number of different areas indicated that the threshold condition for wetting corresponds to a misorientation of about 7 o.
Regions marked A show where the melt has wetted grain boundaries in the alloy and migration of these liquid films has led to grain growth in the outer layers of grains.