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Taking the grinding plane by conventional method will cause a large number of scratches or falling off on the rock surface.
Table 1 Comparison of colloidal invasion and particle size Grain size of emery reference value Particle size /μm W20 2 gram 20~14 W14 2 gram 14~10 W10 1 gram 10~7 W7 0.6 gram 7~5 W5 0.4 gram 5~3.5 W3.5 0.4 gram 3.5~2.5 W2.5 0.2 gram 2.5~1.5 W1.5 0.2 gram 1.5~1 W1 0.2 gram 1~0.5 6.
If the thickness of the thin section is corrected at any time, the grinding thickness of the edge is larger than that of the middle part, and the grain size of the vertical pressure is lighter.

Introduction Recently, a number of various SPD methods that permit severe plastic deformation of materials have been reported in literature (e.g.
A significant grain refinement and the improvement of mechanical properties can be obtained as a result of forming by the SPD methods [4].
Tkocz, Deformation-induced grain refinement in AlMg5 alloy, Solid State Phenom. 191 (2012) 37-44

In subsurface regions, frequent occurrence of cracks along the grain boundaries can be observed on the fracture surface.
The presence of a great number of subsurface defects (cracks, overlapping, etc.) in both the used and the new bolts is evidenced by pictures of longitudinal metallographic specimens (see, for example, Fig.7a,b).
The subsurface ring of intercrystalline plastic deformation testifies to a low cohesion strength of grains in the given region.

. %) such as nitrides (TiN, ZrN), carbides (SiC, TiC), borides (TiB2) and silicides (MoSi2) with composite approach [1], coating the silicon nitride particles with chemical precursors [2] and making the grain boundary phase conductive [3] have been extensively investigated.
To avoid the grain growth of matrix and in-situ formed TiN particles, 1650°C was selected as the maximum sintering temperature for the TiO2 incorporated composites.
Acknowledgement The authors would like to thank to Anadolu University Research Foundation for funding the present work under a contract number of 60266 and also MDA Advanced Ceramics Ltd.

The failure springs were numbered as shown in Fig.3 and their fracture morphology was given in Fig.4.
According to the rule of grain boundary strength and granular strength to temperature, intergranular creep rupture happened at high temperature whereas transgranular rupture at low temperature.
Based on the transition of intergranular origination to transgranular propagation, it was supposed that the spring ruptured instantly when the stress at inner arc section reached the limit for brittle microstructure and low grain boundary strength.

By this way, single crystal copper rod with smooth surface, compact grain structure, excellent ductility and electrical conductivity can be produced.
Under certain supercooling degree, grain density is given by continuous nucleation model of Rappaz and Oldfield [7-8]: (2) Nucleation rate can be described by Gaussian distribution function: (3) where is nucleation number, is maximum number, is maximum nucleation supercooling degree, nucleation distribution standard deviation supercooling degree.
By its chilling action, there are large numbers of crystal nucleuses generated on the contact interface of dummy rod and liquid copper (section “A”).
At the same time, large number of crystals merged together to be columnar crystals toward the heat flow direction.
So, the number of crystal of section “B” decreased obviously compared with section “A”.

During aging, the strength increases as the number and sizes of precipitates increases.
They substantially enhance the diffusivity even at low temperature, however, with ongoing time, the excess vacancies are annihilated at sources and sinks, such as jogs at dislocation or grain boundaries.
We consider the annihilation at homogeneously distributed jogs at existing dislocations with a constant density Hdisl of 1·1011 m/m-3 and the annihilation at grain boundaries with a mean diameter dgrain of 50 µm.
In our case, each sort of trap involves n=12 possible trap positions due to the coordination number of the fcc structure.
Decreasing the quenching rate decreases the number of quenched-in vacancies and, therefore, diffusion is decelerated at low temperatures.

The consequence is that at eutectic temperature, for instance, additional crystallization nuclei occur and a higher number of eutectic cells is achieved.
The number of eutectic cells is also increased, the graphite becomes finer and the cast iron produced has better mechanical resistance features.
Ferroalloys grain size used was 1 - 4 mm.
Finally, iron solidifies with a larger number of graphite lamellae, which have smaller length and width.
Since I1 graphitizing inoculant contains less silicon, the number of graphite nuclei becomes smaller because carbon activity is also smaller.

Number of H2O molecules in the shell of the latter is suggested to estimate according to the peak-to-peak width (ΔBpp) of the broadened ESR pattern.
Detailed analysis of particles with the non-transparent compact core in SNOM image shows up grains marked by an arrow as displayed in Fig. 2.
The size of the grains is mainly varied between 50 and 100 nm.
Thus, only the number of unbroken hydrogen bonds (b) in the aquacomplex and pHb probability define the coupling parameter that is a=pHb·b (a=0.94995·3.9141=3.7182).
Thus, an estimate of number of water molecules surrounding manganese ion in the other complexes can be obtained with eq. (2).

Therefore, the material removal volume in each cycle can be expressed as: (4) After formulas (3) and (4) are sorted, there holds: (5) Where and represent the roughness of workpiece surface in No. i and No. i-1 cycles, respectively; b is the wheel width; is the abrasive diameter; is the cutting depth in abrasive machining. 2α △Lc △Lg Fig.1 Schematic diagram of a spherical grain removal material from workpiece surface dp dg Li为为为为 Work surface Experiment Equipment and Conditions In abrasive jet finishing with grinding wheel as restraint, the grinding wheel stops radial feeding after workpiece grinding and injects abrasive mixture in the grinding area.
Results and Discussion Fig.3 Effect of percentage abrasive concentration on Ra values at different number of cycles Effect of abrasive grid size on surface roughness.
Fig.4 Effect of percentage abrasive concentration on Ra values at different number of cycles Fig.5 Effect of percentage abrasive concentration on △Ra values at 20 machining cycles The higher the abrasive concentration was, the greater number of effective abrasive there was participated in machining, and the stronger the sliding-friction effect on workpiece surface became, which better uniformed and reduced surface roughness and waviness.
The percentage formula for roughness improvement is: Fig.7 Effect of number of cycles on surface roughness percentage improvement △Ra% Fig.6 Effect of number of cycles on surface roughness Ra value at different materials (6) The Ra% values of the two materials in the first several cycles of machining were higher.
Experimental results show that following the decrease of abrasive grain size, the machined surface was dominated by randomly distributed fine dents, and there existed no distinct directivity along machining marks; surface roughness under different abrasive concentrations dropped as machining cycles proceeded, and the surface roughness at the abrasive concentration of 10% dropped the most; surface roughness declined with the increase of machining cycles.