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The surface of grinding and how severe defects after number decreased and ease, but some defects to burnish the ball until the shell is usually also not eliminate board, individual point still more serious.
But not all along the crack grain boundaries produce, Also not along the continuous form grain boundaries, but some have intensive precipitation along the phase or microscopic inclusions from parts of the broken.
Port grain edges keep intact; fracture faces a level off, some on crystal only a small shallow toughening nest.
Carbide triangle and small rectangular shape have M6C carbide grain boundaries in thin strip of grass or pattern.
Analysis Welding residual tensile stress produced under the function of the sliding, in grain boundaries produce larger concentration of stress and strain, including a large number of separation material and inclusion of grain boundaries passivation rupture, show chemical lively fresh metal surface, due to the poor from existing Cr area, in the situation that the poor area under the action of Cr priority dissolve, because stainless steel is of certain itself again passivation and passivation effects, therefore in the situation under the function can make part of the rupture passivation membrane rapid restoration, corrosion in the pit to generate around passivation membrane, then in residual tensile stress continue to function, the den of corrosion due to stress concentration and make the grain boundary passivation membrane rupture, cause the new active anode area, make the grain boundary poor Cr area continue to dissolve.

This serial sectioning technique was used to investigate the recrystallization behaviour of a particle-containing nickel alloy, which revealed a number of features of the recrystallizing grains that are not clearly evident in 2D EBSD micrographs such as clear evidence of particle stimulated nucleation (PSN) and twin formation and growth during PSN.
Figure 6: (a) 2D-EBSD section showing three recrystallizing grains (arrowed).
(a) (b) (c) (d) Figure 6a shows another other set of twinned grains (1 and 2) as well as a fine grain that did not grow during annealing (grain 3).
The pole figure given in Fig. 6b shows that grains 1-2 and 2-3 are twin related and all grains are misoriented 5-15° from the deformation substructure (matrix).
A possible mechanism of formation of twinned grains during PSN is given elsewhere [13].

Introduction Nano-metallic materials [1] appeared in the mid-1980s, which are structurally characterized by nanometer-sized grains with a large number of grain boundaries, occupying over 50 percent of volume fraction.
As the grain size decreases, the volume fraction of grain boundaries is more and more, and whether grain boundaries activities dominate plastic deformation is not sure.
Whether there is an accessible relation between grain size and the wear resistance.
In fact, grain refinement could enhance the friction and wear resistance of materials.
Variation of the friction coefficient with the number of cycle for the SMAT Cu and the CG Cu samples against a WC-Co ball in mineral oil under the given test parameters: normal load of 50 N, frequency of 20 Hz, slip amplitude of 50 lm, and fretting cycle of 72,000 [26].

Exceptions are constituted by rather rare cases, when registered profiles of the X-ray line (hkl) are obtained as reflections from families of crystallographic planes {hkl} belonging to the same grain or to the group of grains with the same orientation.
Thus, the total number of points in obtained diagrams is equal to that in each GPF or in some of its region of interest.
The same number of points is contained in the correlation diagrams.
Grains with the too "spoiled" crystal lattice lose the ability to deform by means of crystallographic mechanisms, so that their final orientations prove to be occasional; texture minima contain only such grains.
Since the rolling texture of Ti-Ni single crystal is very sharp [8], its GPF contains a relatively small number of experimental points, but the indicated tendency is seen distinctly.

The rapid formation of ultrafine-grained structures has been observed in materials susceptible to grain fragmentation upon plastic deformation.
The grain refinement in these steels is accelerated by mechanical twinning and/or strain-induced martensitic transformation [6, 7], leading to the fast development of ultrafine-grained structures at relatively small strains.
The rate of strain hardening gradually decreases with increasing the number of forging passes.
The structural changes are characterized by fast kinetics of grain refinement (Fig. 5b).
Miura, Ultrafine grain development in copper during multidirectional forging at 195K, Philos.

The fine-grained structure samples exhibit higher wear resistance.
The development of metal-reinforced ceramics has produced a group of materials which utilize the novel concept of ductile particle crack bridging of a brittle matrix phase to produce a number of attractive properties for structural application.
The similar grain size and distribution also was shown in Fig. 2(b) and Fig.
Most of pores were located at the boundaries of alumina grains, and some were entrapped in Al2O3 grains.
Alumina grains were grown to more than 2.5 µm.

Influence of Plasticizers on the Properties of Fine-Grained Polymer Concrete F.L.
Properties of polymer concrete mainly depend on the content of the binder, the grain composition of the aggregate, type and content of filler and the hardening conditions.
This paper presents the results of studies of the type and quantity of plasticizers on the properties of fine-grained (sand) polymer concrete.
According to the grain composition and content of dust and clay particles sand belongs to the I class, to the medium grain size group, its properties meet the requirements of Russian Standard 8736 [20].
Microcalcite of MK-100 type with grain size up to 100 µm was used as a mineral filler.

The addition of carbide-forming elements (such as Cr) leads to an increase in the number of grains containing shear bands after warm rolling, a change that can improve the formability of the steel after annealing [3-6].
Bulk texture Deformed grains Recrystallized grains Figure 3.
The common feature for both steels is that the grains nucleated at ferrite grain boundaries were larger than those nucleated within the grains (predominantly at the in-grain shear bands).
For both steels, the grain sizes of recrystallized γ-fiber grains were slightly larger than of α-fiber grains.
Calculations are based on the numbers of nuclei observed.

It is well known that number of zirconium alloys present a breakaway of the oxidation kinetics that is associated to the development of lateral cracking within the oxide [1,2] with microcracks parallel to the metal-oxide interface.
A previous work [7] showed that a mesh with 512 grains is large enough to be a representative volume element, and the grain morphology has no effect on the microstress distribution; classical Voronoï tessellation is then used to obtain equiaxed grains.
In order to compare the second order stresses given by the both approaches, 500 different crystalline orientations have been considered for the modeling of the heterogeneity within the EHM; this is about the number of grains of the polycrystalline aggregate.
The normal stress in the x-direction varies from grain to grain as in the case of the extension in the x-direction.
Number of studies reports the presence of a tetragonal ZrO2 phase (ZrO2t) within the oxide of Zr alloys, even at moderate temperatures [2,4,5].

The growth rate is limited as the number of available nuclei increases more quickly than their size until impingement occurs.
Once DRX has begun during preloading beyond wc, the number of SRX nuclei begins to decrease along with the volume fraction of the deformed matrix and grain boundary area available for the nucleation of SRX.
At the same time, the number of DRX grains growing during unloading by the MDRX mechanism increases with w.
The net number of nucleation sites available for SRX therefore progressively decreases with prestrain, thus weakening the strain dependence of softening.
Beyond this point, the nucleation rate for SRX changes and so does the growth rate that is limited by the number of nuclei.