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Generally, it can be stated that SNCR has a particular impact on the morphology of fly ash’s grains.
The Tescan Mira3 SEM was used to assess the grain morphology of each ERY fly ash.
Before the microscopic analysis itself, the grains of fly ash were coated with gold for better electric conductivity.
Because of this, it can be assumed that the morphology of these grains does not necessarily have to be influenced by its different granulometry.
Optimally built fine particle matrix means the maximum number of contact surfaces of fly ash and cement grains is achieved.

This obtained piezoelectricity was even comparable to the one of textured KNN-based ceramics fabricated by a reactive template grain growth technique.
As seen from Fig. 2(a), some rectangular grain fracture can be clearly observed for pure NKLN ceramics.
However, rectangular grain fracture becomes less and less by increasing NBT content.
Therefore, the changing of crystalline structure will lead to the changing of grain growth habit, then results in modification of grain morphology.
As like as PZT ceramics, compositions near the MPB may have both of these phases coexisting to give a total of fourteen possible polarization directions (eight rhombohedral <111> and six tetragonal <001>), the large number of polarization directions enables optimized crystallographic orientations to be established from grain to grain in the poling process and, in turn, results in high piezoelectric properties [21].

At the triple junction, the grains shrinkage and pore coalescence is likely to occur by increasing the fabrication temperature.
At sintering condition of 850oC and 950oC, the number of pores and pore growth significantly decreased.
Gao et al., [2] also reported that dendritic a-Fe grains left in master alloys can deteriorate magnetic properties of sintered magnets.
Gopalan et al., [1] referred that the grain size strongly affects the coercivity (Hcj) of permanent magnets as the coercivity increases with decrease in grain size which passing through a maximum at some critical value of grain size and decreasing thereafter.
In this study, we didn’t measure the grain size of SPS NdFeB magnet.

This technology can improve the performance characteristics of wore rod and reduce the number of patenting stages during metalware production.
Relevancy Wire rod patenting process is expensive operation for metallurgic enterprise, but using modern controlled cooling conveyor line can reduce the number of patenting stages [4].
During patenting, amount of proeutectoid ferrite (cementite) at the grain edges is minimal, pearlite grains are small with minimal actual distance between the lamels (less than 0.1 micron), providing high strength and plastic properties of wire rod.
Sun, Development of HBR400 Hot Rolled Ribbed Bar with Ultra-fine Grain, Shandong Metallurgy, 2005
Whiteman, Recrystallization and grain growth in hot rolling, Metal Science, 1979

Number of stress relaxation steps adopted in the present investigation is limited by the elongation to failure of both alloys.
Strain hardening phenomenon is related to the dislocation activities within the individual grains and grain boundaries in the materials.
Display of YPE by stress-strain curves of steels [6, 7], Al-Mg alloys [ 8-11], Magnesium alloy [12], fine grained Titanium [13] and ultra-fine grained pure aluminium [14] have already been reported.
Investigations on ultra-fine grained Al rose to a doubt towards the role of interaction between solute atoms and dislocations behind the YPE [14] and supported the claim that occurrence of pronounced Luder bands as a result of concentration of high stresses at grain boundaries [15].
Effect of grain size and distribution on the occurence of YPE as claimed by Li et al. [13] in the case of fine grained Ti is not necessarily be the reason behind occurrence of YPE in the present study, as the average grain size of Cp-TiXT alloy used is a coarse grained material having grain size in few tens of micrometer.

According to the number of elements in the sputtered alloy two- or several-phase films can be prepared. 2.
This means that hard grains (nc-MeN) are not embedded in a matrix of the second phase but the hard grains are separated each from other by a tiny mesh formed of atoms segregated from grains. 3.
The relationships between hardness, average size of grains and microstrain in the film strongly differ for the films with (i) the same orientation of grains and (ii) different orientations of grains, and also for films with larger (>10 nm) and smaller (<10 nm) grains.
A) Ti-Mo-N films with larger (>10 nm) grains The hardness of films with the same orientation of grains increases with (i) increasing size of grains and (ii) decreasing value of microstrain in the film.
Macrostress, grain size, film structure, binding energy, grain boundary interaction, other factors or their combinations?

Understanding major mechanisms affecting material strength such as grain size, grain orientation and dislocation mechanism from atomistic viewpoint can empower scientists and engineers with the capability to produce vastly strengthened materials.
In this follow-up project, the research has developed a coarse graining technique for the multi-scale simulation.
In this regard, the indentation size effect is similar to the Hall-Petch relationship describing the grain size effect on the strength of metals and alloys.
The present results indicate that the critical buckling force and the number of buckles are sensitive to the lengths of CNTs.
Hug, Boron nitride nanotubes with reduced numbers of layers synthesized by arc discharge, Phys.

Beta grain size in cold worked and solution treated condition improves the ageing response [4] by providing more number of nucleation sites for precipitation of alpha phase.
The solution treatment cycles for above sheets are suitably varied to achieve different prior beta grain size.
At the same time, beta grain for the solution treatment temperature of 750°C are finer compared to solution treatment temperature of 780°C which is indicative of grain growth at higher solution treatment temperature.
Further, the tendency to form grain boundary α is more pronounced because the nucleation kinetics of grain boundary α is not as solute sensitive as the kinetics of α homogenous precipitation.
Semiatin and C.H Ward, “Ageing response of coarse- and fine-grained β-titanium alloys”, Mat.

A number of spherical particles up to 200 nm in size are also observed.
Along with grains of 4-8 μm, the local formation of sintered grains up to 15-20 μm is observed.
The average grain size of B4C does not exceed 4 μm.
The average grain size is 8-10 μm with separate large grains of 15 μm.
Along with grains of 4-8 μm, local formation of sintered grains up to 20-30 μm is observed.

Raman spectra in the wave number range of 140–860 cm−1 were obtained using a Raman system (JASCO; NR-1800) with a double spectrometer and a charge-coupled device (CCD) detector.
Most of the grain size is less than 0.5μm , grain boundary is not obvious and there are no cracks on the surface.
But Fig.3(b) and Fig.3(c) show the grain size began to grow up, grain boundary has been corroded out and the surface crack increase as the cycle time increasing.
SEM shows the grain size began to grow up, grain boundary has been corroded out and the surface crack increase as the cycle time increasing.