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A number of reports on the effect of grain size in the manganites particularly La0.67Ca0.33MnO3 have been published [8,9] (and references therein).
The average grain size was estimated using the intercept method.
The electronic thermal conductivity ke can be calculated from the Wiedemann-Franz law, ke = sLT, where s is the electrical conductivity, L is the Lorentz number = 2.45 ´ 10-8 W W K-2, and T is the temperature.
Previous works on smaller grain size (1 to 10 µm) do indeed showed that the thermal properties depend on the grain size.
Hence we conclude grain affected the thermal properties for smaller size but not for larger grains.

The β platelets which were aligned between the recrystallized α grain and the recovered α grain were responsible for the microcrack generation to form (0001) tansgranular facet in the recrystallized α grains.
The microstructure is classified into two regions, which are designated as recrystallized a grain region and recovered a grain region as shown in Fig. 2.[8] The recovered a grains showed a strong texture with (0001)<1120> rotated counterclockwise about 25 degrees around RD (rolling direction) where the highest pole density was about 50 (Fig. 2(b)), while the (0001) of recrystallized a grains were (0001)//ND (normal direction) plane (Fig. 2(c)).
A number of microcracks or voids generated at β platelets in the recovered a grain region, and the origin of (0001) transgraular microcrackings in α grain was usually associated with the β microcracks as shown in Fig. 3(a).[8] That is why the recovered α grains and β platelets behave as ‘softer’ region than the recrystallized α grains under cyclic deformation at very low stress level.[2,12] The traces of the α microcracks shown in Fig. 3(b) were on (0001), which appeared on the microcracking part in the crack initiation site.
In the step (1), the {1010}<1120> slip predominantly operates and developes fairly planar dislocation arrays in the recovered a grains.[11] Slip deformation analysis based on full constraints model by Taylor theory was suggested that internal stress in a grain was developed on the normal to (0001) and hardly relaxed.[13] Since the arrays are piled-up at the boundaries between recrystallized a grain region and recovered a grain region, the accumulated tensile stress along [0001] may develop a local stress concentration in the neigboring recrystallized a grain.
At first microcrack or void was generated in β platelet between the recovered α grain and the recrystallized α grain.

After forging at 1050℃ the grain growth is not obvious and original β grain as well as intragranular lamellar are fine.
The grain deformation is not uniform, there are still undeformed grains.
The grain growth is not obvious, the original β grains and the intragranular lamellar are fine after forging at 1050℃, thus the strength and plasticity at room temperature and high temperature are higher, as a result of the effect of fine grain strengthening.
Fig. 5(b) shows that the fracture mode is a mixture of cleavage fracture and ductile fracture, there are a large number of small and shallow dimples.
The dimple size increases, and the number of tearing ridges decreases, thus the plasticity increases.

The composite material surface was modeled by a set of same radius spherical segments; diamond grains were distributed in the material with a given bulk density.
The authors of the research note the complexity of the problem due to the peculiarities of the ceramic materials microstructure, the roughness of interacting surfaces, contact pressures in the friction zone, lubricant presence and a number of other factors [1, 7, 9].
(6) Here S is the wear zone width, is the speed of mutual movement of the tool and the part; n1 is the number of cycles leading to the separation of wear particles.
Also, when the number of contacting diamond grains increases, the load on each individual grain decreases, and the volume of the ground material changes insignificantly.
It is shown that the grinding performance increases with an increasing sliding speed, applied load and a diamond grain size.

The material flow/deformation characteristics as well as the degree of grain refinement, as a function of different initial grain morphological orientation, vis-sa-vis grain orientation, are studied.
A number of individual optical microscope images were collected throughout a sample from transverse pane of each orientation billets after etched with Krolls reagent (2% HF, 6% HNO3 with distilled water).For TEM observation, samples were sectioned from theflow plane (y-plane) in all orientations billets using a slow speed diamond saw to obtain slices of thickness less than 400 µm.
The microstructure consists of bigger equi-axed grains in the size range 100-200µm with fine equi-axed sub-grains in the range 5-10µm in size.
Within these elongated grains fine, more or less equi-axed grains are observed.
A strong grain to grain interaction leads to strain hardening for substantial changes in end orientation.

The area fraction of the � phase is increased as the pass number increases from 1 to 2 passes and the individual grains become more equiaxed.
Figure 3 plots the elongation to failure against the number of ECAP passes for samples processed with dies having channel angles of �=90 o and 135 o.
For both dies, the elongation to failure increases with an increasing number of passes.
The area fraction of the � phase was increased as the pass number increased and the individual grains became more equiaxed.
(5) Upset testing showed that the maximum formability increased as the number of ECAP passes increased.

The alloys had a coarse-grained structure composed mainly of near-quasi-equiaxed grains of size 10–70 μm.
The numerals indicate the number of complete reduction cycles along three orthogonal directions (a, b, c) and single reduction along the axis a.
Optical metallography reveals both grains with clearly defined deformation traces and grains which are almost free from them.
In the specimens rolled at е = 0.07, coarsening of grains compared to grains in the initial specimens was detected.
At е > 2.0, intense quasiperiodic microcracking began and the number of cracks increased rapidly with an increase in e.

We can conclude that during processing the ultrafine-grained microstructure in as-cast Nb and Ta was formed.
Immediately after EBM, the metals contain a large number of pores (Fig. 4b).
The deformation-induced formation of dislocations, shear bands, and grain boundaries occurred in the metal at the same time.
Viljus, Processing and properties of bulk ultrafine-grained niobium.
Sursaeva, Review: grain boundary faceting-roughening phenomena.

Controlling the grain size is also very difficult in the case of forgings.
In the present study, forged IN 718 alloy having 300 mm grain size is tested at room temperature (RT).
The material shows equiaxed grains with grain size varying from 150 mm to 290 mm.
The loop shape also significantly varied as the number of cycles increased.
Number of reversals.

Fine grain graphite has been an important material for tribologically loaded components such as seals and bearings for almost a century.
Therefore the strategy to improve the strength of fine grain graphite has always been to come to smaller grain sizes and so to smaller voids.
Unlike state-of-the-art fine grain graphite the carbon materials derived from sinterable carbon precursors consist of one single phase, free of grain boundaries.
Overextended milling led to self assembly and agglomeration of the particles thus increasing the grain sizes.
The friction coefficients were in a similar range as for high-end conventional fine-grain-graphite.