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Reaching the mushy zone, liquid is formed by preferential melting at the grain boundaries and penetrates into high angle boundaries of the recrystallized grains.
Circularity of grains as a function of cold working ratio.
According to this phenomena number of recrystallized grain is increased and therefore the average globule size will decrease.
In addition, concentration of solute in the concave parts of grains is higher.
Young ., Fine Grained Metal Composition, US Patent, No. 4(1983) [9] B.

Base material shown in Fig. 2c consists mostly of semi-equiaxed ferritic grains whereas the tramp elements containing DQ materials 0.3Cu and 0.3Cu-0.1Mo in Figs. 2a and b contain a large fraction of more chaotically shaped QF grains with etching-revealed dislocated substructures and possibly carbides, especially in the Mo alloyed steel.
QF grains of the tramp elements containing materials have theoretically the same composition as the parent austenite before the transformation, whereas in the impurity-free base material, the carbon seems to be partially diffused into cementite or M/A constituents in the second phase grains in DQ condition.
Equivalent circle diameter (ECD) grain sizes of investigated steels in coiled and DQ condition.  
Therefore, it can be assumed that the presence of tramp elements increases the amount of abnormally large ferritic grains, but simultaneously the amount of fine sized grains, since the calculated mean ECD grain size is not significantly changed compared to the base material.
Acknowledgement The authors are grateful to Business Finland for funding the project Fossil-Free Steel Applications: Phase II (grant number 5562/31/2023).

The enhancement of elongation is caused by grain refinement mechanism.
The finest grain is obtained at 0.5 % Vf Al2O3.
The grain refinement mechanism at 0.5 % Vf is predicted by well distributed of nano alumina particles in Al-Si-Mg matrix that act as nucleating of grain formation[7].
Furthermore, the smaller grain size is caused by pinning effect of particle alumina that delay grain growth process[16].
Nano alumina particles in the matrix act as nucleation spot for grain refinement because it produces the smaller grain than that of without nano alumina.

Results obtained with HfO2, in form of coarse grain or nano particles, are described.
Eg also decreases with the value of the principal quantum number n of the valence electrons of the free neutral metal atoms.
But, at the same time, the probe ion loses quite a large number of electrons due to Auger processes.
Assuming that the number of mobile electrons available exceeds the number of probes (ce>cp, i.e., f0=1), Forker et al. obtain fV ~0.35–0.4.
However, with increasing temperature, the oxygen vacancies also migrate toward grain-boundary sinks and, as the fraction of Ta probes in the grain-boundary volume of coarse-grained particles is very small, the disordered component in the PAC spectra of cg-HfO2 does not reappear upon cooling.

Titanium is considered to be a ubiquitous element since it has the 9th-highest Clarke number of all elements.
Iron and manganese can also be used as beta stabilizers for Ti alloys, and can be considered to be ubiquitous because of their 4th- and 11th-highest Clarke numbers, respectively.
Only equiaxed beta grains were observed.
Some grains were very large, about 1 mm.
In all of the solution-treated and quenched alloys, only the beta phase was identified, and equiaxed grains were observed. 2.

In this case the grains boundary carbides destroy first.
It leads to the appearance of microcracks in the grains of hard alloy carbides and to the plastic deformation by dislocation mechanism of the cobalt binder [1-4].
They reach their maximum at the points of contact with the abrasive grains and during interaction should occur the destruction of the grains with polydeformational damage of surface.
Divide the signs by a number of elements formed during the processing a workpiece.
As an abrasive used the natural material – garnet brand «garnet mesh 80» with average grain size of 0,180 mm, with hardness of 8 Moh’s which is supplied from the abrasive feed hopper.

Three RX nucleation mechanisms are considered, i.e. cube band nucleation, particle stimulated nucleation and grain boundary nucleation.
The recovery behavior, RX kinetics and final recrystallized grain size are the output of the ALSOFT calculations.
Each weight is simply a real number that is multiplied with the value output from its associated node.
Different ANN architectures, i.e. a combination of varying number of hidden layers and number of nodes per layer were tested, in view of computational speed and accuracy of the predicted flow stress.
Nes, Modeling recrystallization kinetics, grain sizes, and textures during multipass hot rolling, Metall and Mat Trans A, 27 (1996) 4133-4144

He was instrumental in the establishment of an undergraduate curriculum in Materials Science at Oxford, and was an effective leader in the field both through his own scholarly pursuits and his editorial guidance of a number of prestigious scientific journals.
Other papers were concerned with the vexing question of relating the properties of individual grain boundaries to the properties of polycrystals as a whole.
It is our hope that these Proceedings will promote both a better scientific understanding of interfaces and grain boundaries in materials and improvements in the technologies which utilize materials where properties are controlled by interfaces.

The second model takes into account grain growth and cavity formation in addition to the strain and strain rate hardening.
(b) The relationship between the grain size at the pole and strain from bulge forming samples under different pressures.
Following is a relatively more sophisticated constitutive model that has been used in a number of studies [9-14] for superplastic materials.
This model, henceforward called model (2), involves the effects of strain hardening, strain rate sensitivity, grain growth and cavitation: σ=A1-faoeψεdo+Cεnεm (3) where (fao) is the initial area fraction of voids, (ψ) is the void growth index, (do) is the initial grain size, (C) is a grain growth constant, (n) is strain hardening exponent, and (A) is a material constant.
The values of (do=0.0103) and (C=0.0113) were based on the relationship in Eq. (1) between the grain size and the effective strain.

The Urbach energy, grain size, and electrical conductivity increase with Ni content.
(4) where n is the number of the diffraction peaks, I(hkl) and I0(hkl) is the measured intensity and the JCPDS standard intensity data of the corresponding powder for (hkl) plane [19], respectively.
Variation of the grains size of ZnO:Ni.
The increase of electrical conductivity is related with the grain size and leads to a decrease in grain boundaries, which contributes to increasing the mobility of the charge carriers [1,2,3,17,18].
With increasing the Ni content in the solution of precursor sources, Urbach energy, grain size and electrical conductivity are increased.