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Experimental Investigation of Brittle to Ductile Transition of Single Crystal Silicon by Single Grain Grinding F.W.
Grinding is a very complex manufacturing process which is involved with a great number of variables, such as wheel type, wheel condition, operating parameters, coolant condition and machine characteristics.
conducted single grain grinding experiments on a modified wafer grinding machine [6].
Fig. 3 3D image of single grain grinding groove shown in Fig. 2(b) Material response based on subsurface damage.
Therefore, below a critical depth of cut, cracks will fail to form around the cutting grain.

Raulea[3], grain sizes range from 0.016mm2 to 600 mm2.Results show that: yield strength and tensile strength decrease with a decreasing number of grains over the thickness when the grain size is less than the sheet thickness.
This effect can attribute to grain size strengthening or Hall-Petch effect.
If grain sizes became lager than the specimen thickness, the yield strength tend to increase with grain size and a loss of reproducibility is observed.
The grain size is larger, the ratio of surface grain  by the total grain number is larger relatively as foil thickness in constant, effect of surface layer grains on springback behavior can not be ignored.
According to “surface layer model ”,the free surface grains are less constrained and unable to store and transfer  dislocation for the blank of more surface grains, therefore, it leads to the total number of dislocations, grains and grain boundaries reducing in bending process, so the springback angle becomes smaller after unloaded.

EBSD measurements made over a large number of grains as well as macroscopic texture measurements made at different levels of imposed plastic strain allow for comparison against various approaches for predicting variant selection based on the Patel-Cohen interaction energy.
Notably, Humbert et al. did use EBSD to examine individual α’ variants, but only 6 austenitic grains were examined [2].
This would be consistent with the lack of observation of ε-martensite in these grains.
On the other hand, in grains where the transformation appears to follow the γ→ε→α’ two-step path, in particular those grains oriented close to Rotated-brass and Copper orientations [11], the Kundu-Bhadeshia method gave a better correlation between high interaction energy and observed variants.
Indeed, it was shown that the Humbert method predicted negative interaction energies for a large number of observed variants.

Introduction Intergranular fracture is mainly induced by phosphorus (P) grain boundary segregation and loss of grain boundary cohesion [1-4].
Ohtani and McMahon [5] reported intergranular cracking occurs along prior austenite grain boundaries due to the continuity of prior austenite grain boundaries.
The samples showed fine and elongated grain structure along the RD and the prior austenite grain boundaries can no longer be recognized.
The 0.001 and 0.053 %P samples showed remarkable data scattering in absorbed energy at -100 and -150 ºC due to the increase in the number of delamination [13], where the cracks branch parallel to the longitudinal direction (//RD) of the impact test bars.
(b) The crystallographic orientations and (001) pole figures of numbered grains across the crack.

Each level grains the percentage of number or the percentage of quality is tested out.
Accumulative total that is smaller than each size number percentage or accumulative total quality percentage is surveyed out.
(2) The number of the particles at size between x and x + dx is dN: dN= N dyn(x)
Conclusions ·Ultrafine slag grains possessed very well self-similar.
Fractal characteristics of grains are appraised.

The solute diffusion in the liquid and solid phases was also considered in developing a grain growth model.
Dilthey and Pavlik [9] used a modified cellular automaton model to simulate grain morphology.
Simulated dendrite grain growth of Al-7wt%Si alloy.
This is related to the fact that an increase in cooling rate will lead to an increase in undercooling and the number of nuclei activated in one certain domain, which causes the grains to refine.
The program code developed can predict not only the grain structure of the castings but also the textures inside the grains, such as branching, dendrite morphology and eutectic microstructure.

The term ‘‘ultrafine grain size’’ is usually used for the grain size upper than 250 nm.
The number of dislocations piled up against a GB decreases as the grain size is decreased, at a fixed stress level, since this number is a function of the applied stress and of the distance to the source (The sources are assumed to be in the center of the grain, leading to positive and negative dislocation pile-ups generated by the activation of a Franck–Read source) [3].
The mean back stress associated with the loop of a dislocation accumulated at the GBs is proportional to the inverse of the grain size [22], and the net back stress from dislocations accumulated along the GBs is thus expressed by: (23) where M and n are the Taylor factor and the number of dislocations accumulated at the GBs of MC materials, respectively.
The flux of dislocations arriving at a GB per slip band can be calculated as [33-34]: (24) here, is the equivalent plastic strain, λ is the mean spacing between slip bands and is the maximum number of dislocation loops at the GB in the coarse grained metals.
The presented constitutive equation is used to predict the mechanical behavior of MC copper with the unit cell model for which a larger number of experimental data is available.

In the past two decades, a number of researchers have reported on selective corrosion of WC in cemented carbide.
After corroded for 6 hours, WC grains on the surface had been removed completely, leaving a Co layer with WC grains-shaped cavity such as triangular and square shaped cavity on the surface.
With the increase of WC grain size, WC corrosion content decreases.
When corrosion time were 2 hours, the coarse WC grains were found on the surface while the fine grains have been removed completely.
It supports the effects of WC grain size on corrosion rate.

Grain boundary phases in Mg-Zn-Y-Nd-Zr alloys subjected to various heat treatments were characterized.
The mean grain size D determined by the linear intercept method is given in Table 1.
The a-Mg grains which appear dark in the image due to lower Z are surrounded by Zn and Y enriched eutectic which appear bright due to higher average Z number.
The Zn and Y enriched regions at grain boundaries consisting of W and I phase are denoted by the term grain boundary phase (GBP) in the following text.
DSC peaks for various processes are labeled by numbers.

The grain refinement strengthening can be generally described by a Hall-Petch equation [9].
The grain size decreases with the increase of pass number.
Fig. 3 shows the variations of friction coefficient with pass number.
Fig. 3 Variations of friction coefficient with pass number.
The decrease of wear volume of the alloy after ECAE with pass number is mainly due to the improvement of mechanical properties caused by grain refinement.