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%H2O) to display the grain boundaries.
From the dark-flied image taken from 1/3(211)β, a large number of fine precipitates (~5nm) are visible (Fig. 2(b)).These precipitates refer to athermal ω phase , which is formed due to shuffle transformation during rapid quenching [17, 18].
After aging treatment, a large numbers of α precipitates which separate out of the β matrix strongly increase the strength.
However, due to the existence of GB α phases, the cracks nucleate in the voids of grain boundary and propagate along the grain boundary (Fig. 6(b-d)).
At aging conditions, the cracks are nucleated from TiB phase located in the grain boundary and propagated along the grain boundary of α phase

The coarse grain heat affected zone (CGHAZ) contains mostly intra-granular nucleated ferrite plus a few grain boundary ferrite and ferrite side plate, and shows charpy impact toughness ≥ 90 J at -40 °C.
FL contains grain boundary ferrite (GBF), ferrite side plate (FSP) and intra-granular nucleated ferrite (IGF), and the prior austenite grain size was estimated to be 100~120 mm.
FL+5 mm shows a mostly PF grain structure, which corresponds to sub-critical HAZ.
A large number of inclusions are found at HAZ, and typical morphology and composition were shown in Fig. 7.
This kind particle has a size range of 0.3~3 mm and a number density of 4.3×104/mm3.

The average dislocation path distance is calculated as: (6) where: A1- coefficient from the range (0,1), Dgr – grain diameter calculated as: (7) where: Su – surface area of a single CA cell, Dp – apparent grain diameter calculated from: (8) where: ngr – number of cells in a particular grain.
The cell (i,j) under consideration is additionally represented by a random number ξ (0, 1) and it can become a nucleon only when a probability condition is fulfilled ξ < wnucl.
Microstructure morphology after DRX at T = 875 K and initial grain size equal a) 54 μm (final grain size = 38 μm), b) 44 μm (final grain size = 39 μm).
Microstructure morphology after DRX at T = 975 K and initial grain size equal a) 54 μm (final grain size = 57 μm), b) 44 μm (final grain size = 74 μm).
Szyndler, Effect of number of grains and boundary conditions on digital material representation deformation under plane strain, Archives of Civil and Mechanical Engineering, In Press, Corrected Proof, Available online 29 September (2013) [16] L.

A large number of processes to achieve such deformation have now been developed, and the benefits and advantages of each process are under continued debate [1-3].
In this way A* can be regarded as a multiple of a certain number of dislocation cells within the microstructure.
One approach that can be taken is to focus on the largest grains/dislocation cells and to ask the question of whether the number of such large grains is consistent with a continuous coarsening process.
For example, for an ideal Rayleigh distribution of grain sizes the mode occurs at a value of dmode ≈ 0.8 dav, and only 1.1% by number of grains (approximately 6% by area) will have sizes greater than 3 dmode.
Consequently, if a microstructure developed after a short annealing is found to have a significantly larger number of grains with size greater than 3 dmode, then this can be taken as an indication of a distributed, but locally non-uniform process.

The coating cycles in each series are indicated by the number following the series type.
Two types of grains are observed on the film surface: small grains with ~10 nm diameter above the underlying layer having grains with ~100 nm diameter.
The PySC decreases with increasing number of coating cycles (layers) in all series.
Therefore, different trends of the PySC indicate that the lead loss is a function of the layer thickness and number.
The PySC decreases with layer number (larger overall thickness), however it increases with the larger thickness of individual layers.

The total quantities of the grain are presented by the following: v l g f V N v = (4) where fv is the volume ratio of the grain, Vl is the volume of the diamond layer, vg is the volume of the grain.
Quantities of the grain per area are defined to be 23 a vN N= (5) Here, Nv is the quantities of the grain per volume, ( v v g f N v = ).
The effect of volume ratio of the grain affecting thickness of the oxide film is direct proportion.
An increase in the impulse width with increasing electrolytic circle number, is followed by an increase in the thickness of the oxide film.
The oxide film was thickening with the increase of volume ratio of the abrasive grain.

The S–N curves (i.e., plots of the maximum stress of applied cyclic stress (S) versus the number of cycles to failure (N)) of the strips were plotted, where the fatigue strength (i.e., fatigue limit) was defined as the maximum stress at which the specimen did not fail in 2 × 106 or more cycles.
Inverse pole figure maps and grain size distributions of the strips are shown in Fig. 3.
Inverse pole figure maps and grain size distributions on RD–TD plane of TRC AZ31 strips with thicknesses of (a) 1 mm, (b) 1.5 mm, and (c) 3 mm. davg denotes the average grain size.
This behavior can be explained by the difference in the grain sizes of the strips.
The average grain size of the strips increases with an increase in their thickness.

Optical microscopy was used to examine the recrystallized grain structure.
Grain structure after the intermediate annealing and after the brazing heat treatment.
Fully recrystallized grain structures were observed after the intermediate annealing and the brazing heat treatment, but these grain sizes were distinctly different especially for the salt bath annealing.
Considering the increase in the number of fine particles with the brazing heat treatment, the Mn in solid solution in the salt bath annealed sample would be consumed in precipitates during the brazing heat treatment.
(1) A sufficiently coarse grain structure was attained after the brazing heat treatment in both intermediate annealing processes, and the salt bath annealing promoted further coarsening of recrystallized grains

A number of machine parts have a design notch or component of notch pattern for the discharge of their own function.
Ra=0,26 mm;Rt=2,33 mm, 0 cycles Ra=0,17 mm; Rt=1,44 mm, 2.105 cycles Fig.1 Surface profile changes after dynamical load 2.105 cycles (42 hours), material bearing steel 100Cr6, ground by SG grains Fig.2 Microhardness changes in surface, bearing Fig.3 Change of residual stress course at working steel 100Cr6, SG grain load 5 and 78 hours, ground by SG grain, vc= 30m.s-1, vp= 0,26 mm.min-1, synthetic coolant- Diol Present calculation method Fig.4 Network of boundary elements on sample, Fig.5 Stress concentration in notch root fatigue crack runs from notch The calculation of machine parts with design notches (also stress raisers) is based upon elastic factor of the stress concentration kt [11].
The ground neck will be characterized probably by tensile residual stress; it will depend on the type of used grain.
Table I. – Machining of sample surface and notch Machining of surface Grain size at grinding Feed speed Cutting speed vc Notch machining Cutting speed vc turned SC (sintered carbide) 0,05 mm/rev. 94 m/min turned SC 94 m/min turned SC 0,05 mm/rev. 94 m/min ground CBN 40 m/sec ground SG 150 1 m/min 40 m/sec ground SK 94 m/min ground SG 150 1 m/min 40 m/sec ground CBN 40 m/sec ground CBN 125 1; 3 m/min 40 m/sec ground CBN 40 m/sec There were the cyclic load used 630-550 MPa and 600-520 MPa in this experiment.
Fig.8 Affection of cyclic load time with machining method –SC (sintered carbide), SG (microcrystalline corrundum grain), load cyclic stress 630/550 MPa Fig.9 Dependence of surface roughness Ra of ground notch on number of load cycles, cyclic stress 630/550 MPa The surface ground by SG grain with ground notch by CBN (cubic boron nitride) approves the longest durability in occurrence of ground surface with ground notch.

The SnO2 doping can enhance the ZnO grain growth that lower the breakdown field of doped samples.
Due to the melting point of SnO2 is about 1127oC [12], at higher sintering temperature more foreign species are precipitated at grain boundary with grain growth, hence the less Zn substitutions make insignificant donor behavior.
Since the I-V property of varistor controlled by the Schottky barriers at grain boundary, this may indicate that the SnO2 doping will promote grain growth, the SnO2 doped samples have less grain boundary junctions in series, hence the less number of Schottky barriers in serious which cause the lower breakdown voltage.
Furthermore, the large ZnO grain, grain boundary phase and spinel phase (small particles) can be clearly seen (especially in Fig. 3c).
Evidently, the SnO2 promoted the ZnO grain growth, the higher the SnO2 doping level, the larger the ZnO grain growth.