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An example of similar structures is found with the wood- being flexible in bending normal to the grain direction and quite stiff along it.
It is determined by a presence of oxide layer on the grain surfaces, very small contact area between adjacent powder grains and large number of contacts over the electrical path.
Semi-sintered powder conductivity is still extremely low despite the fact that a number of solid bridges are generated between the grains.
Three-scan strategies in EBM with additional melting of already solidified layers allow achieving smaller grain sizes and better distribution of carbide precipitates in the iron-based materials.
Babu, "Site specific control of crystallographic grain orientation through electron beam additive manufacturing", Materials Science and Technology 31 (2015) 931-938

Introduction Environmental and economic considerations lead to efforts to cut the number of manufacturing operations in production of steel.
As a rule, they exhibit very fine-grained structures, which provide excellent toughness and resistance to fatigue.
L03 specimen was cooled too slowly, which left sufficient time for the grains to grow.
Microstructure with too large austenite grains is not suitable for strain induced martensite transformation.
Such grains transform at too low magnitude of strain.

To obtain an adequate fine-grained final microstructure, the strict control of thermomechanical processing and accelerated cooling is also crucial [4-6].
This results from the higher density of substructure and dislocations within the austenite grains, which increases the nucleation rate of acicular ferrite [8,11,12].
On the other hand, it is known that the refinement of ferritic microstructure is enhanced by a fine-grained austenite before transformation, and especially by a microstructure of strengthened austenite with elongated grains, high dislocation density and ledges in the grain boundaries that increases the density of nucleation sites and promote high nucleation rates for ferrite [4,13].
Results and Discussion The torsion test gives the values of torque applied versus the number of turns made on the specimen, which are transformed respectively into equivalent stress and strain using Von Mises criterion [17].
However, the sample that was quenched from heavily deformed austenite kept a microstructure of relatively acicular ferrite with enhanced grain refinement.

Considering the effect of anisotropic inter-facial energy, an energy form adopted by Kobayashi [5] was used: (9) Where is a parameter about interface width, is a angle between the normal to the interface and the , , , which is the angle between the crystallographic axis and x-axis; is a random number between , is the magnitude of anisotropy.
Herein, noise was introduced by modifying the phase field equation (10) Where is a random number distributed uniformly between -1 and 1, and at each time step, is an amplitude of the fluctuations.
In the simulation of simple grain growth effected by fluid flow, the two dimensional square calculation areas of 500× 500 grids for phase field and solute field were meshed.
Micro structural evolution effected by different anisotropy In the Fig.1 (a), the multiple dendrites growth showed the impingement of arbitrarily oriented grains, and the grains began to impinge and coalesce the adjacent grains with time going on, the dendrites distributed symmetry obviously.

The grain shapes and sizes were also typical, with no boundary deformations due to stress or strain loads.
Fig. 12 Specimens investigated with SEM and EDAX (credit Roxana Trușcă, Vasile Bogdan, National Centre for Micro and Nanomaterials) The investigation of the specimens was carried out with SEM, for the study of the surfaces’ appearance and with backscattered electron imagery, for the alloy’s grain structure analysis.
Fig. 14 SEM micrography of fractured area (credit Roxana Trușcă, Vasile Bogdan, National Centre for Micro and Nanomaterials) Fig. 13 SEM micrography of undamaged area (credit Roxana Trușcă, Vasile Bogdan, National Centre for Micro and Nanomaterials) The microstructure investigation of the specimens was conducted using backscattered electron images, that showed brighter contrast microareas which correspond to the heavier (i.e. greater atomic number) elements and darker contrast microareas, for the lighter (i.e. smaller atomic number) elements.
The analyzed specimens microstructure of primary aluminium dendrites and substantial amount of different intermetallic phases constituents varied in shape, size and distribution (i.e.: needle, plate-like or “Chinese script”) These are located at the grain boundaries of α-Al as a dendritic network structure.
The grain shapes and sizes were also typical, with no boundary deformations due to stress or strain loads.

The mills have similar shape but different number of sectors and different diameter and weight.
The diamond grains have the same properties of granulometry and Advances in Materials Manufacturing Science and Technology 470 grain shape.
Table 1 Mill properties Shaped mills Mill properties M1 M2 Chemical composition of bond [%] Co Cu C O Al Si Diamond mesh [#] Diamond concentration [Kts/cm ] Tool weight [g] Tool diameter [mm] Sectors number Length of sector [mm] Depth of sector [mm] Width of sector [mm] Core diameter [mm] 62.40 17.79 14.09 3.14 1.24 0.98 45/50 120 612 59 16 46 4 6 51 25.59 49.89 16.71 3.89 2.34 1.58 45/50 156 543 54 12 46 4 8 46 Fig. 1 Shaped diamond mill Fig. 2 Example of sequence of curve cuts A series of curve and free-form surface machining tests were carried out on slabs of a stone with dimensions 1500mm×850mm.
Due to harder bond involving higher strength for retaining the diamond grains on the tool surface, higher volume of materials removed by each single diamond grain before it has invalidated or pulled out.

For this reason, a number of research are being done by developing binary[7-9]and few ternary oxide systems [10-12],so that the ductility or toughness of the material could be improved.
It is not only the number of components in a system that affect the properties of the composite, processing method also does.
The EDS patterns confirm that the brighter, finer grains are ZrO2 and the darker, larger grains correspond to Al2O3.
Based on the XRD analyses shown on the figures, mullite and zirconia particles with sub-micrometer in particle size are mainly located at grain boundaries, while finer ones were within matrix grains, inferring that larger mullite and zirconia particles suppress grain boundary movement of alumina matrix.
In addition, from this work it is observed that the increase in fracture toughness is solely correlated to a larger grain size, until the optimum grain size is reached.

Ca, as a grain refining addition to Mg–Al-based alloys, has also been proved to be effective in improving high temperature strength and creep resistance in Mg–Al alloy.
One can see that the phases were precipitated along the grain boundaries and the grain size was between 5-10um and the phases were join together as meshy like.
The finer of the grain was, the stronger of the alloy was.
In this experiment, the grain dimension was 1-2um, so it has a intensive effect on the yield strength of the Mg alloys.
The overall result is that the total number of particles decreases and the mean radius increases with time and temperature.

�egative effects caused by recrystallization In final products, extensive examinations have shown that fatigue life time is reduced in recrystallized vs. fibrous condition, and coarse grains are worse than fine.
In recrystallized microstructure with large variation in grain size, fatigue life is less predictive and design has to be conservative.
Performance of the material is even worse when recrystallized grains grow and precipitates are growing.
However, the formation of recrystallized grains will only occur if the sub grains are able to grow larger than a certain size, RC.
In AlMgSi1, a combination of Mn and Cr is often used to maximize the number of dispersoids in order to minimize the recrystallization susceptibility.

Because peak current density of PC electrodeposition is considerably higher than the average current density, the rate of crystal nucleation is higher than that of crystal growth using DC electrodeposition, thereby leading to a decrease in the size of the grains of the coating, tight arrangement of the grains, and decrease in the number of pores [1~4].
The corrosion current density of the inert anode prepared by pulse electrodeposition is lower one half than that of DC electrodeposition, showing the inert anodes prepared by pulse electrodeposition has better corrosion resistance.Because pulse electrodeposition with higher instantaneous current density can increase cathode activation polarization and decrease cathode concentration polarization, causing that the grains sizes is decreased and the structure defects are reduced.[9~11].
The structure of Pb grains prepared by DC electrodeposition is that of octahedral, but the compactness of the deposit was not high, the grains sizes is larger and there exist some obvi- ous structural defects.
Compared to the anode inert prepared by DC electrodeposition, the grains are regular, the structural defects are few for the inert anodes prepared by pulse electro- deposition.
These particles can play a role in grain refinement and increase the active sites amounts of electrochemical surface used for oxidation- reduction transition when they are dispersed uniformly in Pb grains or between grain boundary, the electrocatalytic activation of the inert anodes is improved .