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Pressure measurement film was employed to detect effective grain cutting edge.
Microphotographs of truncated diamond tool (Grain number #100/120) are shown in Fig. 6.
Marks in the pictures show truncated grains.
Experimental results of the effective grain cutting edge detecting were shown in Fig. 7.
Results show the effective grain cutting edge area of diamond tool was spread by cutting edge truncation.

People usually refined, modified α-Al phase and eutectic silicon in the structure by adding trace elements before pouring the molten alloy to improve the mechanical properties of the alloy, and many trace elements, the most sensitive to grain refinement, the most obvious refining effect is the B.
%,α-Al dendrites significant refined, refinement degree than the first two should be sufficient, but the B content is 0.077 wt.% when the grain distribution is more uniform than when 0.044 wt.%, dispersion , more closely.
There are a small number of dimples on the section, while there is a quasi cleavage plane.
Because in the smaller values of the secondary dendrite arm spacing of sample, cracking of silicon particles appear preferentially at the grain boundaries, cracking path is mainly controlled by the inter-granular fracture.
Fracture surface showed that the fracture of the alloy are the mixed fracture of trans-granular fracture and grain boundary fracture caused by the second phase, there are many different sizes of the number of dimples on the fracture surface of alloys, has been a marked dimple fracture characteristics.

TEM analysis reveals near the same grain size in nickel nanowires.
The main part of grains extends across the diameter of the wire.
In a 20 nm wide nanowire we can see one grain only, while there are two grains possible in nanowires with dw=40 nm.
Dots (red) indicate the experimental MH curve for the big number of hexagonal arrays.
Difference in experimental and theoretical MH curves is due to shortage of computational capability allowing to model the small number systems only.

During UPM machining, the mill grains in electrolyte attack the surface of workpiece repeatedly and continuously under the action of ultrasonic.
The mill grain attack the workpiece surface in electrolyte under the effective of ultrasonic wave.
In process of a mill grain attacking workpiece surface under ultrasonic, the maximum load on workpiece surface P is [5]: 2 5 6 5 3 5 2 2 2 0 1 0 1 2 1 1 2 2 2 4 1 1 4 5 3 4 h f V A e P R E E V α ρ ν ν πρ ρ − −     − −   = +            （4） Where 1E , 2E and 1ν , 2ν are elasticity modulus and Poisson ratio of the mill grain and workpiece respectively, 1ρ and 2ρ are density of mill grain and medium, 1V and 2V are the ultrasonic velocity in the electrolyte liquid and in the polishing head, f is the frequency of the ultrasonic vibration, 0ρ is the density of the polishing head, 0A is the vibration amplitude of the polishing head, 0p is the sound pressure of initial ultrasonic, R is the radius of mill grain, α is the attenuation quotient of ultrasonic in electrolyte liquid.
( ) ( )( )2 1 2 3 4 2 2 1 2 2 3 3 h L C V C C P H P K π πξ ξ = = （8） The quantity of removal material by ultrasonic in unit time is: ( ) 12 5 4 0 h M NBR A e α− ΙΙ' = （9） Where MΙΙ' is the quantity of removal material 3ρ is the density of workpiece, ( ) ( ) 1 2 3 2 2 2 1 3 2 3 C B A H A K πξξ ρ= , B is consistent while the workpiece material is determinate, N is the effectual number of mill grain in unit time, N is consistent while the electrolyte flow rate, size of mill grain and machining gap are determinate.
Using diamond as the mill grains, quenched steel as workpiece, we carry on a series of experiments, and select a set of appropriate processing parameters, which include the size of mill grains, ultrasonic vibration frequency and vibration amplitude, the machining gap between head of ultrasonic vibration tool and the workpiece, pulse electric current for the polishing results in UPM-PECM compound finishing.

Vogel model is shown as follow: (1) Where, n is the ordinal number of the sunflower kernels. m is constant parameter.
A lot of abrasive grain blocks are ranged over the surface of the polishing pad according to the phyllotactic pattern of the sunflower kernels.
From the Fig.6, the contact pressure will be changed when the diameter of the abrasive grain block is increasing gradually.
And the uniform region of the contact pressure distribution in the center will be enlarged gradually with the increasing of the diameter of abrasive grain block.
When the diameter of the abrasive grain block is D=Φ2.0~2.2mm, the contact pressure distribution can become uniform.

In literature there is a number of publications showing the structure of TRC strips of varying thickness and obtained from various grades of aluminium alloy (although these mainly discus alloys that are most popular for this technology, namely the 1XXX, 3XXX and 8XXX).
The tilt angle of the grains increases with an increase in the casting speed and in the flow of the coolant.
Macrostructure showing the distribution of grains during the process halt with a visualization of the lower part of the finished strip, the area of the TRC hollow and the flow system shows that the fine grains at the surface are formed during solidification in contact with the roller.
The structures of strips observed in the longitudinal cross-section have long pillar-like grains, which converge at the centre of the strip, and the axes of grains are inclined with respect to the strip axis, and the direction of their growth corresponds to the heat transfer direction from the metal (the tilt of the grains increases with an increase in the casting speed and in coolant flow, and depends on the amount of deformation in solid state).
Birol Y.: The performance of Al–Ti–C grain refiners in twin-roll casting of aluminium foilstock, Journal of Alloys and Compounds, 430 (2007) 179–187 [8].

A large number of test methods have been employed to study reheat cracking in Cr-Mo steels, which can be classed into the following three categories [16]: (1) Tests on complete weldments, e.g.
With the increase of wH from 200 to 1000℃/s, both the primary austenite grain size and bainitic laths size decrease (Fig. 3b~3d).
With prolonging tp from 0.5 to 2s, the grain size and bainitic laths are coarsened in some degrees (Fig. 3e, 3d and 3f).
The simulated 15 kJ/cm heat input sample gives primarily M + small amount LB, with grain size approximating 55μm.
The simulated 60 kJ/cm heat input microstructure is composed of LB and a small amount of granular bainite (GB), with grain size approximating 110μm.

Fig. 2: Unique grain color map.
There are two statistical distributions which are important for describing the structure of polycrystalline materials, namely the distribution of grains by crystallographic orientations (texture) and the distribution of grain boundaries by misorientations (grain boundary spectrum).
By applying the present method and increasing the number of Gauss points a converged solution will be obtained.
The measured SEM/EBSD data (see Section 2) such as e.g. crystallographic orientations, grain sizes and misorientations as well as number of slips and number of twins are used in the CPFE code (micro level).
This is due to the heterogeneity of the material that is a result of the mismatch between grain orientations and grain anisotropy.

Matrix grains will impose the compressive stress (σM) on the solid lubricant particles (Fig. 4).
On the contrary, the matrix grains will also suffer the compressive stress (σTC) from the solid lubricant particles.
The volume of the separated out solid lubricant can be determined by the equation as follow: 1— Matrix 2— Solid lubricant particle 1 Ra 2 σM σM σM σTC σTC σTC (6) Fig.4 The thermal stress diagram of the element of the self-lubricating materials Where ∆V1 is the volume expansion of matrix grain around the solid lubricant particles, and ∆V2 is the volume expansion of the solid lubricant particles, and α1 and α2 are the coefficients of volume expansion of the matrix grain and the lubricants particles respectively, and T is the temperature of friction surface, and V1 and V2 are the original volume of the matrix grain and the lubricant particles respectively.
On the area of 1mm2, the number of the solid lubricant particles can be calculated by the condition: 19.5n≥S×H.
If the thickness of lubricating film H is 0.1μm, the number surfaces of the solid lubricant particles on the area of 1mm2 is: n＝105/1.25＝8×104.

The Laves phase was nucleated mainly on prior austenite grain boundary (PAGB) and lath martensite boundary at the early stage of aging.
On the other hand, increase of aging temperature decreased the number density of precipitates.
Increase of time led to a slight increase in the number density of the Z-phase.
Figure 3 showed typical TEM micrographs of lath structure, large precipitates and sub-grain in both specimens.
Typical TEM micrographics of lath structure, large precipitates and sub-grain.