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The material adopted in the present work is the coarse-grained CP iron with a number of micro-voids pre-existing at grain boundaries (GBs).
Tanaka [19] has reported that the fractal dimension of the fracture surface profile was correlated with that of the grain boundary when the grain boundary was fracture path.
The initial microstructure of the CP iron consists of large size grains (~200mm) and a number of micro-voids (in the size of several microns) pre-existing at GBs, as shown in Fig. 1.
Experimental results and discussion The cyclic stress response curves of the coarse-grained CP iron at different Dεt/2 are presented in Fig. 2.
With increasing number of cycles, the specimen undergoes a continuous cyclic hardening and no saturation stage occurs due to a continuous crack propagation as a consequence of strong interactions between dislocations and micro-voids at GBs.

It is necessary to study the reservoir heterogeneity of the number 2 of shanxi Formation in this block for concerning the unfavourable extraction condition.
The study indicate that reservoir plane heterogeneity of the number 2 of shanxi Formation in study area presents the medium to slightly strong characteristics in general.
The shanxi Formation can be classified to number 1 and number 2 basing on lithology characteristics.
The main sandtone types are medium-to coarse-grained containing gravel or seriate grain rock-fragment sandstone, lithic quartz sandstone and quartz sandstone.
The sedimentary system of the member 2 of the shanxi Formation is a marine braided river delta whose reservoir is mainly distributary channel sand body and the reservoir space is a combination of holes between grains, dissolved pores and micro cracks.

Using stronger ultrafine grained material increased the load and reduced the pin height uniformity.
Micro-billets have lower yield strength for surface grains, different metallurgical orientation of the grains results in less uniform material flow and large surface grains increase friction due to open lubricant pockets at the billet end surfaces.
To overcome some of these problems it is possible to use ultrafine grained (UFG) metals (average grain size less than 1 μm) in preference to coarse grained (CG) metals (grain sizes 10-300 μm) [2].
The findings of the simulations can be used to significantly reduce the numbers of iterations required to successfully produce micro pins in large numbers while improving pin height uniformity.
This obviously occurs earlier for less dense arrays as less material needs to be extruded from the billet into a smaller number of pins.

In both cases, the ultrafine grains were developed in the samples.
The elongation was not affected significantly by the number of ARB cycles in both cases.
However, such ultrafine grains are not developed in the sample of CR-ARB.
Tensile strength of the samples processed by the CR-ARB increased with the number of ARB cycles.
Lee: Ultrafine Grained Materials 2, Edited by Y.

As the Na2O was added up to a maximum of 2 mol%, the number of abnormal grains and the grain size increased.
All the grains (the abnormal and the matrix grains) have faceted boundaries as shown in Fig. 1 and 2.
The 5 mol% Na2O sample consists mostly of equiaxed matrix grains and no abnormal grains are present.
Comparing 0 and 0.5 with 1 mol% Na2O excess samples, it can be seen that the number of abnormal grain increases with Na2O addition.
Therefore, the number of grains that show abnormal growth is increased.

Abstract: Recrystallization of rolled Zr single crystals is considered in comparison with analogous recrystallization processes in rolled coarse-grained iodide Zr.
Fig. 3 shows reorientations of prismatic axes {1120} due to recrystallization in the rolled Zr single crystal (a) and of the coarse-grained iodide Zr (b), both rolled by ~80%.
Hence, twinned crystallites are characterized with low strain hardening and contain relatively small numbers of recrystallization nuclei, growing at the expense of neighbors.
Namely here, grains are localized, deformed by participation of two or three different slip systems, i.e. prismatic, basal and pyramidal ones [3].
The greatest number of recrystallization nuclei forms in α-Zr grains plastically deformed by operation of different slip systems, as in crystallites corresponding to stable orientations of the rolling texture.

The varistor voltage increases with increasing number of ZnO grain boundaries between the electrodes.
Thus, to fabricate varistors with low breakdown voltages it is necessary to reduce the number of ZnO grain boundaries between the electrodes.
It has been reported that adding only Ba or Ti to ZnO promotes grain growth enabling large ZnO grains to be obtained [4,5].
Addition of 0.25 mol% Ba did not promote grain growth, but Ba addition above approximately 0.35 mol% did promote grain growth.
However, Ba is uniformly distributed at grain boundaries despite the non-uniform distribution of Bi at grain boundaries.

This observation should be attributed to the addition of grain refiner C2Cl6.
It is worth noting that the grain size of the AM60 alloy is reduced by almost two times in the C2Cl6 treated specimen due to the grain refinement effect of the C2Cl6 addition to the alloy.
With the addition of the C2Cl6 powders, the number of nuclei and nucleation rate increases.
Average grain sizes of AM60 and C2Cl6 treated AM60.
The melting temperature of the AM60 alloy was also reduced by the grain refiner.

Surface bump, cracks and other damage morphology accompanied by a large number of twinning organizations were found in the four-point bending test of magnesium alloy.
Prepare a number of lath-shaped samples of AZ31 magnesium alloy with the size of 160mm×6mm×12mm.
Under the tensile and compressive stress, a large number of bump appeared on the surface of magnesium alloy.
More coarse magnesium grains, more obvious bumping.
Also, smaller grain size is conducive to the twin deformation and grain boundary sliding which helps further coordination of twinning, while larger grain size is conducive to twinning, but not conducive to grain boundary sliding.

It is mainly of ferrites and a large number of uniformly distributed fine lath martensites.
Thereby a large number of grains were broken into sub-grains, resulting in a large number of nucleus during the process of recrystallization.
Thus, they were kept in the fine grain condition.
There appears reply recrystallization and grains growth, which is the main reason to promote MS1470 steel HAZ grains coarsening.
After the heat treatment, the average grains size becomes 10μm.