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Several abrasive processes were created that are able to offer surface finishing better than conventional lapping can provide, which is time consuming and difficult due to the great number of variables.
The 800 mesh grinding wheel had fewer loose grains, followed by 600 and 300 mesh, respectively.
The smaller the average abrasive grain size, the higher the dressing power.
Except for Ud = 5 and the 300 mesh grinding wheel, the major lapgrinding powers were found for the 800 mesh grinding, possibly due to the larger number of active cutting edges.
The results showed that the smaller the average grain size, the lower the workpiece surface roughness.

Phases in the interdendritic regions or near the grain boundary changed continuously with time at the bonding temperature.
It can also be seen that the number of coarse γ' decreases with increasing temperature.
Fig.13 shows changes of the microstructure in the dendrite boundary or the grain boundary at 1453K.
At temperatures below 1423K, it can be seen that eutectic phases near the grain boundary region are still present.
It is clear that the crack is due to liquefaction at the grain boundary region.

The smallest grain size of prior austenitic grain was after Alloy1, ASTM 6 Alloy2, ASTM 6 Alloy3, ASTM 7 Alloy4, ASTM 8 Fig. 3: Structures and grain sizes of the test alloys after 1075 °C 30min + 750 °C 2h.
In Alloy4, grain sizes increased significantly.
At the same time, grain coarsening was observed in boron-containing alloys.
In parallel, grain growth occurred.
Harries, High-Chromium Ferritic and Martensitic Steels for Nuclear Applications, ASTM Stock Number: MONO3, ISBN 0-8031-2090-7, 2001

The polished samples are etched by Keller’s reagent（22mLHF+10mLHNO3+88mLH2O）to disclose the weld structural detail including grain boundaries and grain contrast.
The β phase is distributed along the boundaries of the α grains.
The HAZ near the fusion line contains a large number of acicular martensite due to the relatively high temperature in the thermal cycle process.
It displays that the laser power plays a more important role in the degree of grain growth.
If heat input is larger, the grains become coarse and the microhardness is decreased.

Grain refinement is simulated by forcing the element size to zero.
They concluded that the load was increased with the number of ECAE process.
Grain refinement which is the main feature of ECAE process can be simulated by enforcing the elements size tends to zero.
A number of tensile tests were carried out at 200°C for identification of material constants.
This issue simulates the grain refinement which is the most important feature of ECAP process.

DEM can represent the ceramic at the grain scale by particles bonded together, and the damage is represented as broken bonds or grains explicitly and naturally.
In order to represent the complex-shaped grains of SiC, we make a number of particles bonded into a cluster (see Fig. 1).
Here we set the maximum allowable number of particles in a cluster equal to 7, and different color represents the different cluster.
But it also can see that the propagation of cracks was along the grains boundary in the inside of material, which illustrated that the mode of fracture of inside materials was inter-granular fracture.
The number of residual cracks in the workpiece after the cutting of SiC obtained under different pre-stress conditions was plotted in Fig. 3.

The volume fraction of the recrystallized grains was used as a kinetic parameter.
Results and Discussion 60 % cold rolled sample exhibited a microstructure with elongated grains along the rolling direction shown in Fig. 1.
It can be observed in these micrographs that the volume fraction of recrystallized grains (equiaxed grains) increased with ageing time and finally after about 60 minutes the process of recrystallization is nearly completed which led to 100 % recrystallized grains structure.
In a solid state transformation large number of atomic processes occurs and the rate of each atomic process is exponentially related to the activation energy/enthalpy and reciprocal of the absolute temperature [4].
The micrographs in figure 2 (a and b) confirmed this where the recrystallized grains are not uniformly distributed.

Larger grains tend to lead to rougher as-deposited surfaces, while columnar grains may lead to lower transverse fracture toughness or may lead to enhance transverse thermal conductivity.
Automated algorithm was carried out on separated grains.
We calculate the grain diameters assuming a log-normal distribution (1) of experimental data where A is an arbitrary constant, depending of the number of particles and xc is the maximum of the distribution
All of three types of coating have fine almost spherical grains and a smooth surface morphology.
Results for morphology of multi-component films Multi-component Thin Films Substrate Mean Grain size Shape of the grains Single (Si) Glass 15.35 Spherical Silicon 17.47 Spherical Binary (SiC) Glass 22,45 Almost spherical Silicon 123,82 Almost spherical Ternary (SiCAl) Glass 21.20 Almost spherical Silicon 55,35 Stainless steel 33,72 Acknowledgment This work was supported by a grant of the Romanian National Authority for Scientific Research, CNDI– UEFISCDI, project number 160/2012, PN-II-PT-PCCA-2011-3.2-1453.

It is the instantaneous high current density that makes the metal ions reduction in the high overpotential, which makes the sediment grain thinner.
The analysis results show that average current density is small, the amount of deposited metal is less and the number of the nanoparticles that be embedded in Cu-ZrO2 composite is limited.
Meanwhile, the nanoparticles embedded in the Cu-ZrO2 composite inhibit the growth of grains in base metal, which makes the grains in the Cu-ZrO2 composite fine, structure compact and thereby plays a fine grain strengthening role.
In addition, the grains in base metal will be further refined and the content of ZrO2 in the Cu-ZrO2 composite increases due to the pulse electroforming process own characteristics, which all contribute to futher strengthen grain refinement effect and dispersion strengthening effect.
Under the effect of ultrasonic, the obtained nickel coatings are in fine crystal grain size.

It was characterised by equiaxed γ grains of about 20µm, containing annealing twins.
However, they are useful to analyse the main trends of the martensitic transformations within a large number of γ grains.
It can also be noted that grains being less transformed often correspond to small grains or to annealing twins.
Thus, the orientation factor and probably the grain size influence the transformation rate of a γ grain.
Under these conditions, the model predicts during the initial stage of straining, a complete transformation of austenite grains, belonging to the Cube and Goss components whereas the grains belonging to {110}<111> and Copper components are not transformed.