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ORIENTATION GRADIENTS IN a-FIBRE GRAINS OF COLD ROLLED IF STEELS P.
The plastic response of the rotated cube grains under cross-rolling (total reduction 60%) revealed the occurrence of a certain crystal fragmentation process located at the grain boundaries of rotated cube grains.
In the present investigation in-grain strain heterogeneities are observed in rotated cube grains (cf.
For the present calculation the number of grain boundary planes is limited to those being representative of the lamellar microstructure resulting from a plain strain compression deformation (i.e. rolling deformation).
Acknowledgements This research was carried out under the project number MC5.07294 in the framework of the Research Program of the Materials innovation institute M2i (www.m2i.nl).

Bulk production with high accuracy can be realized by these technologies, but costs are comparably high and the number of different materials is quite limited [2].
Thus, metal forming technologies become more and more demanding in the production of micro parts and a number of investigations are currently being done in recent years.
The physical meaning of T/D is the total number of grains across the material thickness.
Since the number of grains in cross-section area are less than 20 grains, the decreasing trend in the flow stress curve may be related to the smaller constraint among the grains .This can be explained by the increasing relation of surface grain to grain inside the materials.
That is because the grain number in the cross-sectional area is less than 20 grains.

Vickers Hardness vs. mean grain size.
(a) CG Ni with a mean grain size larger than 10 µm; (b) as-deposited NC Ni with a mean grain size smaller than 30 nm and heat-treated NC Ni with a mean grain size of about 60 nm.
The length of the dislocation source may be some fraction of and proportional to the grain diameter, because they are associated with individual triple lines or grain/grain interfaces.
As l scales with the grain size, the AV value increases with increasing grain sizes.
The shear strain, γ, is defined as tnr /2πγ = where n is the number of turns, r is the radius and t is the thickness of the specimen [58].

A number of hillocks on the film were formed after air annealing at 500 oC for 30 min and few things in N2 annealing.
Tin oxide films have been fabricated by a number of techniques, including spray pyrolysis, sputtering, chemical vapor deposition (CVD), and evaporation.
A cauliflower grain means an aggregated grain of crystallites, and the crystallite means the smallest grain with grain boundary.
However, if the grains of the film are composed of many crystallites as shown in figure 2, the migration of crystallites of a cauliflower grain is easier than that of one whole cauliflower grain because it needs less driving force or stress.
The standard specimen was sintered at 700 oC for 2 hrs and the grain size was about 200 nm.

Zhu, Heterogeneous lamella structure unites ultrafine-grain strength with coarse-grain ductility, PNAS 112(47) (2016) 14501-14505
Another issue when discussing pure metals is the fact of limited numbers of defects (vacancies, dislocations and grain boundaries) contributing to strain hardening.
Kaibyshev, On nature of grain boundary recovery, Phys.
The mechanical properties were examined at room temperature after HPT processing through different numbers of turns and at elevated temperature of 250 °C.
Microhardness of bulk titanium evolves typically for HPT-processed bulk pure metals increasing in 4-5 times with increasing numbers of total revolutions.

Si denotes one of the Q possible grain orientations number at site i.
Sj represents the orientation number of site j which is the neighbor of site i.
The above steps are repeated until the desired evolution step number is reached.
The radius of grain is calculated as , where V is the volume of one grid and A is the number of grid points within the grain.
The orientation number Q of lattice sites for matrix phase ranges from 1 to 200.

Introduction Grinding is a special machining process with large numbers of parameters influencing each other, which can be considered as a process where thousands of irregular cutting edges interact simultaneously with the workpiece at high speed.
From this point of view, a number of single grit micro-cutting tests were conducted [1, 2].
The abrasive grain is a conically shaped diamond grain with apex angle of 140◦ and nose radius of 0.06mm.
Grain/Work Interface 2.
The values of the critical depth of cut are, therefore, effective for separating the cutting grains and plowing grains when the grain-workpiece engagement condition is determined from grinding kinematics simulation. ����������������_��������������_���������� = ��������������_����������/�� (3) where, Ac is the cross-section area of the grain, as shown in Fig. 2(a).

Three grains, Grain 3, Grain 4 and Grain 5, were only in contact.
At the grain boundary between Grain 3 and Grain 4, strain distribution continued smoothly.
In contrast, discontinuous strain distribution was found at the grain boundary between the Grain 4 and Grain 5.
Mean strains in Grain 1 and Grain 2 were almost similar.
Acknowledgements The SR experiment was performed with the approval of JASRI through proposal numbers 2005B0019 and 2007B1213.

In low doped BaTiO3 the grain size is around 1-3 µm, while in ceramics with high dopant content (1.0 at%) the grain size distribution was in the range of 3-10 µm.
Introduction Because of intrinsic capability of perovskite structure to host the ions of different radius size, a large number of different dopants can be accommodated into the BaTiO3 lattice.
Manganese as additive segregates at grain boundaries and can prevent grain growth.
A number of studies are confined to the effect of additive and grain size on the ferroelectricparaelectric phase transition [10-12].
For 0.1 at% doped ceramics a small-grained microstructure (1-3 µm) is observed, while for 1.0 at% doped ceramics the grain size is ranged from 3-10 µm.

Within each melt pool, the grain size is not uniform and some finer grains are distributed around the large elongated grains.
The degree of grain refinement generated is evaluated by estimating the ASTM grain size number and then correlated to the average grain diameter of the weld section.
Fig. 5 SEM microstructures of the welds produced at different heat inputs and cooled under normal condition: (a) 432 J/mm; (b) 518.4 J/mm; and (c) and 1296 J/mm Fig.6 SEM microstructures of weld samples produced by cryogenic cooling and then welding at different heat inputs (a) 432 J/mm; (b) 518.4 J/mm; and (c) and 1296 J/mm Fig.7 EDX spectroscopy of welds produced under different welding conditions: (a) welds cooled under normal condition; (b) samples cooled in liquid nitrogen prior to welding Effect of cryogenic Cooling on the Grain Size of Weld The grain diameter is evaluated through intrapolation within the spectrum of the ASTM grain size number and is given in Fig.8.
The grain structure of welds is primarily determined by the time spend above the grain coarsening temperature.
The grain refinement was between 14% and 36% compared to the grain size of the welds cooled in normal condition.