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The addition of rare earth Ce can increase the number of hard phase and thus produce more crack initiations, so that the mechanical properties of HMn64-8-5-1.5 brass can be reduced.
Rare earth Ce is a common additive of refining copper alloy grain [7,8].
Fig. 2 Average size of HMn64-8-5-1.5 brass matrix grain with different content of Ce The addition of rare earth Ce into HMn64-8-5-1.5 brass can refine matrix grain, and the effect of refining grain can be more evident with an increase content of Ce.
It contributed to the formation of new grain nucleus, but not to the growth of grain [13,14].
The reasons of refining grain are as above.

Ti inoculation level was changed up to 0.1wt% by adding Al-10Ti master alloy into 3003 aluminum melt as grain refiner.
A number of components are press-formed at room temperature and then assembled to a net shape.
An Al-10Ti master alloy was used for grain refining of 3003 alloy, and the consequent effect of grain refinement on strength and formability of the clad aluminum sheet was examined through tensile tension test and hemispherical dome stretch test.
Grain refinement significantly increased the biaxial formability of the 4343/3003/4343 clad sheets by 2 times or more.
It appears that an isotropic and fine grain structure was more favorable to biaxial formability.

Because of the plastic bond, the number of active abrasives will increase and the abrasive cutting depth will become even and small [1].
Simulation results showed the number of point regions in the minimal cutting depth decreased to zero rapidly.
But detection results showed that the number of point increased in the minimal cutting depth range.
The number of point regions in zero cutting depth was most (4500 Pts).
The number of these fine grains will decrease to zero with the grit size decreasing, so the point regions in minimal cutting depth dropped to zero in simulation.

The number of grains containing in-grain shear bands, increased with decreasing deformation temperature; after deformation at 600 °C or 550 °C bands were observed in every grain but at 750 °C or above, shear banding was detected only in some grains.
In-grain shear bands appeared to be intense in the g-fibre grains, but also grains with other orientations contained in-grain shear bands.
The highest number of nuclei formed at the original grain boundaries – especially at triple junctions, although nucleation also took place readily in the in-grain shear bands.
Reheating to 950 °C and immediate cooling was sufficient to produce large number of small recrystallized grains.
Evidently however, the number of grains containing in-grain shear bands decreased with increasing deformation temperature.

This processing produced ultra-fine grained (UFG) structure with an average grain size of 0.6 μm and an average dislocation density of ~4×1014 m-2.
However, there were a limited number of reports dealt with examination of superplastic behavior of Cu alloys [1,2,4].
Grains and (sub)grains contain a large number of lattice dislocations (r~4×1014 m-2) (Fig. 1b) [10].
The formation of significant number of annealing twins occurs during dynamic grain growth [1] (Fig. 7b).
Acknowledgements The financial support received from the Ministry of Education and Science, Russia, under Grant No. 14.575.21.0005 (ID number RFMEFI57514X0005) is gratefully acknowledged.

The FΣ3 parameter has been defined as the relative number of high angle boundary segments, in the range from 15º to 65º misorientation, satisfying a Σ3 relationship within a fixed tolerance.
In-grain level: Different OIM options have been used here to define parameters that can be related to the in-grain microstructure.
θθθθm [º] F[1º,15º] K [º] OSA [º] Related distance ∆d ∆d 2∆d Over the grain Table 2.
Conclusions The effect of monotonic and strain reversal conditions on the microstructure has been studied at two levels (grain boundary and in-grain).
Proceedings of First International Conference Recrystallisation and Grain Growth, Eds.

The number of total atoms was set to be 731640.
Thus, the MD calculations indicated that grain boundaries act not only as barriers for dislocation motion but also as dislocation sources, which implies that grain refining increases the number of dislocation sources.
The effect of increasing in the number of dislocation sources on the BDT behaviour will be discussed next, basing on the dislocation shielding theory.
Michot[22] pointed out that the BDT temperature depends on the number of dislocation sources and spacing along a crack front.
It is therefore concluded that the decrease in the BDT temperature by grain-refining is due to not the decrease in dislocation mobility with respect to short range barriers but the increase in the number of dislocation sources around the crack.

The abrasive mixture was boron carbide powder with grain number F400/17, mixed with kerosene and machine oil with grain concentration equal to m = 0.25.
Normally those two surfaces interact indirectly via abrasive grains.
Grains are cutting tools during lapping.
Hence, the abrasive mixture used in this research was boron carbide powder, grain number F400/17, mixed with kerosene and machine oil with grain concentration equal to 0.25.
Normally two surfaces interact indirectly via abrasive grains.

The gradual reduction of grain size with increasing ultrasonic output power can be attributed to an increase of the nuclei number formed in the initial crystallization period.
The average grain size was 120µm.
With increasing the treating time, the grain size of the alloy was reduced.
In this way, a large number of nuclei can be produced during the expansion stage.
Thus, the grains of the Mg-3.0wt.

The cold working process multiplied the dislocations and led to the grain fragmentation.
The cold working process multiplies the number of dislocations in pc metal, which are arranged the network with a low angle misoriented cells within coarse grain interior at the center of the specimen where the moderate equivalent shear strain εv is .
The succeeding strains progress the fragmentation of grains.
The saturation of grain refinement is achieved by an equivalent strain of for nickel [1].
It is noteworthy that there are large angle grain boundaries for the uf microstructure.