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Asymmetrical distributions show bleached and unbleached grains.
HF was used to remove most of the feldspars and to etch the surface of quartz grains.
After that few grains (<1 g) of feldspar contaminated quartz subsamples remained.
A different number of aliquots were measured for each sample.
However, further research on a higher number of lime mortar samples with different origin and ages is needed to study the problems found in this first insight.

The grain is considered as an uniform region neglecting the formation of the dislocation microstructure.
The grain undergoes a strain eII (with a stress sII) composed of an elastic part ee and a plastic part ep.
The elastic strain rate is linked to the stress rate in the grain through the Hooke’s law: (5) where s is the elastic compliance tensor at the grain level.
is the accumulated slip in the cell in the grain I .
This number of crystallites has been chosen to simulate the polycrystalline aggregate in an efficient way.

Microstructural evaluation of the alloy plates revealed that due to FS welding, fine and fragmented dynamically recrystallized grains have been formed in the weld nugget.
Introduction In the former undivided Soviet Union, additions of the transition element Scandium (Sc) have been used for a number of years as an alternative grain refiner to Ti/TiB2, particularly in the context of welding.
Some of the claims have recently been confirmed in the west and finer grain sizes have been reported in Sc-refined castings.
Grain refinement due to the addition of scandium has been previously shown to arise from the precipitation of primary Al3Sc particles in the melt, which act as potent nucleation sites for aluminum grains [1].
The reduction in the size of the particles and increase in number density of the particles would have also responsible for enhancement of tensile properties of the welded joint.

Analysis of Crack Propagation Behavior in Alumina with Different Grain Sizes Under Static and Cyclic Fatigue H.
Crack propagation in high purity alumina ceramics with different grain sizes was investigated with the Double Torsion method during static and cyclic fatigue.
At low loads, the crack growth rate is initially equal to zero, but crack bridging decreases monotonically with the number of cycles.
Crack bridging in coarse-grained AKP19 alumina Crack bridging degradation under cyclic loading.
Thus, the compliance function could be monitored first as a function of the number of cycles, without any crack propagation.

The deformation texture was simulated with the grain cluster texture model GIA ('Grain Inter-Action'), which is a Taylor type texture model that takes grain interaction into account.
After discretization of the starting texture into 4000 single grain orientations assuming triclinic sample symmetry these grains were randomly grouped into clusters of 8 grains each.
Besides the deformation texture, the number of different slip systems NGLS activated during the complete deformation in each grain, the relaxed deformation tensor history ( ()trelaxedijε& ) of each grain, and the total amount of shear relaxation in each grain ( relaxshear vM − ε ) were important output quantities of the GIA model for downstream simulations [6,11].
Finally, a high number of different active slip systems NGLS in grains was connected to faster ODR kinetics, essential to form viable GB-nuclei [6,11].
The relative contributions (Frand, FGB and FTB) of the three distinguished nucleation mechanisms to the total nucleation texture were based on the frequency of the related sub-structural features, i.e. the number of grains with shear bands nrand, with fast recovery kinetics nGB, and with TBs nTB, respectively.

In representative regions, average grain diameters of 600-1000 individual grains were measured to determine average grain size (results equivalent to intercept method, ASTM E112-113).
The composite μ-map indicates presence of both fine grains and heavily elongated grains in the specimens deformed in the region A.
(a) (b) Fig. 2: a) Composite µ-map : Numbers- average grain size (µm), white lines – heavily elongated grains, loops (A), (B), (C) – unstable domains ; b) Flow instability in Region A (b) (c) (a) Fig. 3: a) Q2 composite µ-map; abnormal growth in instability regions b) (B); and c) (C) Qualitative examination of microstructure obtained from regions (B) and (C) shows no signature of instability/ To address this, the individual components of microstructure have been studied in isolation.
The resulting microstructure contains some large grains and several small grains (Fig. 3(b)).
Since grains of Q3 and Q4 groups are larger in size than those of Q2 group, it is expected that the Q3 and Q4 grains (of specimens from the region C), are a result of abnormal grain growth.

When the grain size increases, the grain boundaries density decreases; consequently, the carrier diffusion by the grain boundaries is also reduced.
The optical band gap increases because the crystallinity of the film increases and also due to the increase in grain size.
CZT1, CZT2 and CZT3 showed pebble-like crystal grains with mean diameter about 50 nm, 200 nm, 250 nm, respectively.
CZT3 had staggered and strip-shaped structure with the average grain size of more than 500 nm.
According to (a), (b) and (c), it can be seen that as the substrate temperature increased, the grain size grew.

For the 4P 1050/ 6082 and 4P 6082/1050 FSPed joints, table 2 summarizes the average grain size measurements of the mean grain sizes, standard deviations, minimum and maximum grain sizes of the surfaces depicted in Figure 3.  
The 4P 1050/6082 mean grain size joint ranged from 5.381 to 9.120 µm, while the 4P 6082/1020 mean grain size ranged from 1.744 to 1.193 µm.
Dynamic recrystallization occurred as the number of FSP passes increased, causing grain size refinement.
The following conclusions were reached based on results archived; findings are as follows: · The grain sizes were decreased as the number of passes were increased.
The 4P 6082/1050 had substantially finer grains than the 4P 1050/6082

The high fracture toughness contributed from not only mechanism of crack deflection, crack-bridging and pull-out by a large number of fine TiB2 platelets, but also the ductile toughening result from plastic deformation of Cr-Ti-Al metallic phases.
Super high sintering temperature results in the abnormal growth of TiC-TiB2 grains, so the fracture toughness of TiC-TiB2 composites is still at a low level [1].
FESEM images and EDS results showed that a large number of randomly-orientated, fine TiB2 platelets were uniformly embedded in the irregular TiC1-x grains, and Cr metallic phases were located between TiC1-x and TiB2 crystals, whereas a few of α-Al2O3 inclusions were also observed, as shown in Fig. 2.
Fine TiC grain has certain resistance to crack propagation due to the increase of fracture surface energy and presents a classic cleavage fracture behavior, so TiC grains should be controlled in size as finely as possible.
Tailoring of phase assemblage and grain morphology of (Nd, Dy)-containing SiAlON powders prepared by combustion synthesis, Mater.

The grains boundaries is β-phase (Fig 5a).
In some grains equiaxed α-phase are found (fig. 5c) [22].
HIP was conducted for a decreasing of pores and inside defects numbers.
Grains size influence from fractional composition.
Microstructure DLD metal contains fine acicular α-phase inside β-grain.