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The Effect of Magnetic Field on Kinetics of Grain Boundary Grooving in Iron E.
It was shown that external magnetic field of 5 kOe slows down the kinetics of grain boundary grooving in iron at 750 °C by about one order of magnitude.
The average grain size after this high-temperature annealing was 30 µm.
AFM topography image (a) and the line profile taken along the white path (b) for Fe sample annealed for 2 h at 750 °C in magnetic field of 5 kOe. 0 1 2 3 0 10 20 30 wc=1.75 µm (a) Number of GBs w, µm 0 1 2 3 0 20 40 60 Number of GBs w, µm (b) wc=1.01 µm the magnetic field leads to the diminishing of size of the GB grooves, which, according to Eq. (1), is associated with the decrease of surface diffusivity.
Watanabe in "Recrystallization and Grain Growth", G.

With this segmentation, we obtained statistics on macropores on intact and deformed Indiana limestone which shows that inelastic compaction was followed by a significant reduction in the number of macropores.
A number of isolated blobs (in red) can be identified in the macroporosity zone.
There is an overall decrease by a factor ~2 in the number of macropores with respect to the undeformed rock (Fig. 5).
The partitioning between solid grains, macroporosity and the intermediate zone dominated by microporosity are shown.
With this segmentation, we obtained statistics on macropores on intact and deformed Indiana limestone which shows that inelastic compaction was followed by a significant reduction in the number of macropores.

However, the tensile fracture surface of as-extruded alloy has a large number of small dimples besides cleavage planes and tear ridges, as seen in Fig. 8 (b).
Secondly, the grain refinement makes the grain rotating and grain boundary sliding easier.
Due to the different orientation of each grain, the deformation of each grain is not at the same level.
The interaction force among adjacent grains causes the mutual rotation of the grains.
The grains were effectively refined after hot extrusion.

Fig. 2(a) shows the microstructure of the as-extruded sample (N=0) showing equiaxed grains of an average grain size of (50 ±10) µm.
The final grain size at N=4 results indipendent from the starting extrusion grain dimension.
Fig.5d illustrates the hardness variation with the number of ECAP passes for the two investigated alloys.
In particular, radius number 10 always shows the lowest value.
In fact there is a progressive increases in hardness with the number of passes for the alloys up to the same values when N=4.

The quality of the steel depends on additional factors which cannot be deduced from its grade number, e.g. the manufacturer and the processing route comprising smelting and melting, final annealing and the treatment of semi-finished products.
In a great number of cases, the short life of dies from tool steels is often the consequence of inadequate thermomechanical treatment.
The values in fine-grained areas were almost 40 HV3 higher than those of coarse-grained areas.
The parameter value is obtained by dividing the time, over which the part cools down from 800 to 500 °C, by the number 100.
The weakening of the boundaries of grains is also evident from the manner of crack propagation: cracks propagate along grain boundaries in the so-called intergranular fracture (Fig. 8).

�-fibre grains (ND-fibre grains) are, in general terms, more fragmented than �-fibre grains (RD-fibre grains).
This technique enables the orientation of deformation bands, the misorientation across them, the orientation of the new recrystallized grains and the misorientation of those grains with the adjacent matrix grains to be determined.
In zones 3 and 4 a great number of low angle boundaries (<15°) parallel to RD originate, which intersect with the microbands running perpendicular, as can be seen in the image quality map.
The orientations of the recrystallized grains numbered from 1 to 9 in the figure and the misorientation angle/axis with respect to neighboring zones are gathered in Fig. 3-c.
Conf. on Rex. and Grain Growth, Trans.

Preparation of Porous LSM/YSZ Composite with Varying Grain Size of YSZ Precursor Using Solid State Reaction Method Romar Angelo M.
In order to increase the TPB sites in the SOEC, the number of voids which would allow the infiltration and exchange of gas should also be increased.
The use of a pore former decreases the conductivity of an electrode but in theory, a less-dense anode will perform in terms of reaction kinetics because of the increase in the number of active sites for electrolysis [1].
The nanoYSZ precursor grains cause a higher density which resulted to a possible higher total conductivity.
Conclusion The effect of YSZ precursor grain size and the presence of graphite pore former on the properties of LSM/YSZ were investigated.

“top-down” systems of the grain refinement process.
In the present work, the initial material shows a uniform and quasi-polygonal grain structure with a mean grain size of 12 mm (Fig.1).
Results and Discussion Although the effect of precipitation on microalloyed steels' mechanical response has been studied by a number of scientists [15,16], limited research has been performed so far on the role of fine second phase particles and solid solution strengthening of UFG structures.
EBSD grain boundary maps of the specimens after AAD+WD+WF; near surface –a); centre – b).
Kirchheim, Grain coarsening inhibited by solute segregation, Acta Mater. 50 (2002) 413-419

from the grain surface towards the neck formed between two grains.
Here, the neck growth of two spherical grains of equal radii r=0.2 is investigated.
The case investigated here concerns two grains in contact.
The fact that each grain has its own material properties is an additional difficulty: each grain (or group of grains), must be described by its own a level set function.
An Eulerian description of the problem where the ceramic grains (without restriction concerning the number of grains), evolving in a fixed adapted mesh, are described by using a level-set method is the key point of the numerical simulations.

The results indicated that the fracture of the rod is induced by the unqualified chemical composition: a large number of inclusions which distribute in grain boundaries reduce the material plasticity and toughness, and eventually cause fracture.
The segregation of s along grain boundaries can weaken the gain boundary strength and induce the embrittlement eventually.
A large number of inclusions can be observed homogeneously distributed in matrix from Fig.4.
The results indicated that matrix metallographic structure is ferrite and pearlite, and the grade of grain size is 7-9, whether horizontal or vertical section.
(3)A large number of inclusions which distribute in grain boundaries reduce the material plasticity and toughness, and eventually cause fracture.