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The grain size of Specimen #4 shows much finer grains with the minimum size reaching about 1 micron.
During the transformation, the carbon atoms diffuse to the grain boundaries with the growing ferrite grains to form carbon-rich retained austenite foil in the grain boundaries.
This might indicate why the grain boundaries are rough.
Wung, Grain Fining Theory and Control Technology of Ultrafine Grain Steels, Metallurgical Industry Publisher, Beijing, 2003 [3] W.Y.
Choo, New Challenge to Develop Ultra Fine Grain Steel with 1micron Grain Size, J.Kor.

This grain element is connected by grain boundary element to account for shear deformation between grains.
This grain element is connected by grain boundary element to account for shear deformation between grains [8].
Grain Boundary Element.
In FE model, the numbers of grain element and grain boundary element are 910EA and 1132EA, respectively.
Grain element is used to analyze the deformation of individual grains while grain boundary element is for observing the sliding, extension and grain boundary effect.

Abnormal grain growth is a discontinuous process, where a small portion of grains consuming the neighbor grains become selectively much larger than the latter.
It is true that the major driving force for abnormal grain growth is the reduction in grain boundary energy, but an additional driving force may be needed to overcome the circumstance that normal grain growth is being inhibited [5].
It is obvious in the early stages of grain growth that abnormal growth of the <111>//ND grains is distinguished as compared to the other oriented grains.
Existence of solute atoms to inhibit normal grain growth is a necessary condition for the occurrence of abnormal grain growth.
Also the concentration profile of sulfur atoms having an affinity for boundary segregation can be changed along the thickness direction without a great modification of the microstructures since the nanostructures contain a large number of interfacial areas.

The most important characteristic of corundum is very high hardness (number 9 on Mohr scale).
It is referred in the Mohs scale as number 9, and thus represents the second hardest mineral after the diamond.
Sample number 1 is dust of white corundum, which is made by suction from un-magnetizing process e.g. removing free iron.
Sample number 2 is also white corundum, however its origin is from suction dust from manufacturing hall with drilling and separate machines.
Especially fine grain materials (grain size is in nano and micro meters) is a valuable indicator of quality.

Computer Simulation of Grain Coarsening During Liquid Phase Sintering Z.
As the grains grow beyond the critical point pores start to decrease.
Our model assumes that for each pore there is a critical grain size required for filling.
As a consequence of grain growth, pores start to decrease because liquid flows into them.
A decrease in the number of pores (Fig. 3) and an increase in the average contour size with simulation time (Fig. 2) are evident.

Mechanisms of Deformation Behavior of Coarse-Grained and Ultrafine-Grained Ti Igor Alexandrova, Roza Chembarisovab Ufa State Aviation Technical University, 12 K.
A grain size is known to be one of the factors which define mechanical properties of metallic materials.
The coefficient of annihilation of the screw parts of dislocations , determined from the experience, according to [9] is equal to , (4) where is the share of the screw part of dislocation loops (), is the number of slip systems (for HCP metals ).
The grains contained a high dislocation density and other crystal lattice defects.
In connection with this the grain size has changed inconsiderably and made up 197 nm.

The permeability of coarse-grained soil is influenced by many factors.
In practical projects, the number of engineering accidents caused by seepage at home and abroad is also very large.
There are many factors that can decide the seepage properties of coarse-grained soil.
Coarse-grained soil that got in a hydropower station dam is artificially burdened into 12 samples to study on the permeability coefficient of coarse-grained soil.
The particle size of soil sample is 0.0~60mm and the sample is numbered 1-1~4-4.

Changes in grain size, texture and misorientation distributions have been monitored during extensive normal grain growth in 3%Si steels.
The latter data were based on grain reconstruction with a minimum disorientation of 5º used to define a grain boundary.
The peak orientation density shows a slight decline during grain growth.
Fig. 6(b) presents limited misorientation measurements from recrystallised colonies which show that excessive numbers of low angle boundaries are already present at this stage.
Arita et al. [9] reported a similar profusion of low angle boundaries in a 0.5% Si steel when it had coarse grains prior to cold rolling and annealing but not when the prior structure was fine grained.

The equivalent strain produced by HPT, e, is estimated as [3] (1) where r is the distance from the center of disc (or ring), N is the number of revolutions and t is the thickness of disc (or ring).
Fig. 4 Grain size at steady state plotted against shear modulus.
Figure 4 shows that the grain size tends to decrease with an increase in the shear modulus.
HVS: steady-state hardness, G: shear modulus, dS: steady-state grain size, b: Burgers vector.
The hardness and grain size reach steady-state levels at large strains where the hardness and grain size remains unchanged with further straining.

Mechanical Properties of Aluminium Wires Produced by Plastic Consolidation of Fine Grained Powders.
The standard mechanical properties of extrusion products have been determined and grain structure has been inspected.
Rapid solidification of pure aluminium can provide material with refined grain structure in form of powder or flakes.
In addition, the numbers of micro inclusion of aluminium oxides are present in both coagulated and thin layers form placed along the boundary of fibres.
Pre-compaction of powder does not change the structure of extruded wires, although the number of inclusion of oxides seems to be greater for non-compacted state.