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In the past, a considerable number of works have been done in order to improve the resistance to corrosion because the chemical stresses were the most critical.
It is used for hard thermal shock, i.e., for Biot number Bi >> 1 (Bi > 40).
“Structures” parameters (geometry and load) are hidden and are indirectly present in Eq. 1 through the Biot number.
For example, for the alumina graphite refractory, the weak zones are located either in the carbon matrix or at the grain interface.
The different types of damage occurring are highlighted and moreover, it is easily possible to examine the influence of the nature of the grains.

It is shown from Fig.2a that the primary α-Al is in the shape of dendritic without Sr modification, where the grain shape is irregular and the grain size varies widely and the eutectic area distribution is relatively concentrated.
There was a large number of short rod-like eutectic silicon, and the boundary was sharpened while the Sr content dropped to 100 ppm.
Thus, the poor strength and plasticity will be obtained due to the shrinkage cavities, porosities and coarse grains defects [15].
Effects of processing parameters on the performance of Al grain refinement master alloys Al-Ti and Al-B in small ingots.
Effect of grain refining and Sr modification interactions on the impact toughness of Al–Si–Mg cast alloys.

With proper segregation of molybdenum to the grain boundaries, the hardenability increased [1].
Nb inhibits recrystallization at low temperatures due to the formation of Nb(C,N) via strain-induced precipitation, and at high temperatures due to the solute drag effect on the grain boundaries.
The same precipitate types with large numbers were observed in the simulated samples with CRs 5 and 60 °C/s which were formed by strain-induced precipitation besides the formation of a few numbers of BN along with Al2O3 as shown in Figure 6a.
Acknowledgement The authors would like to thank Interreg Aurora for their financial support, project number 20357962.
Kubota, Atomic-scale study on segregation behavior at austenite grain boundaries in boron- and molybdenum-added steels, Acta Mater. 133 (2017) 41–54

According to study by Gao, the loess could be divided into three types as weak cemented loess, half cemented loess and cemented loess based on the grain composition, the consolidation and the weather conditions of the loess when it formed.
The structural loess could be divided into three different types as weak cemented loess, half cemented loess and cemented loess based on the grain composition[3], the consolidation and the weather conditions difference of the loess when it formed.
Tab. 1 Parameters of loess samples Sample Sampling Site Initial Void Ratio Water Content (%) Grain Composition (%) Clay Silt Sand LZ Lanzhou 1.12 4.5 17.3 68.2 14.5 GY Guyuan 1.15 5.4 17.3 73.2 9.5 QS Tianshui 0.98 16.5 30.5 62.8 6.7 The loess samples after being dried were formed into small sheets with a square centimeter in size, and coated with gold film on their surface.
As seen in the figure, overall, the dynamic strain of the structural loess increased with the cyclic times increase, it grows slowly at first, and is gradually accelerating when the εd=0.5%, as well as rapid increased and broken in a very limited cyclic number when the εd>3%.
However a number of studies have suggested that pore water pressure of structural loess cannot reach the effective confining pressure due to the dissipation effect caused by dissolve of the water-resisting and cementing material of small or medium-sized closed pore.

The composite material's high electric and thermal conductivity made it ideal for use in a number of power plant applications.
The structural properties of copper grains at 66 mm sized particles are often smaller than those of copper grains near 420 mm sized particles.
Because grain boundaries increase phonon scattering and create micro-strains, grain size reduction can definitely play a role here [38]. 3.4.
It was discovered that adding the right number of diamond particles to Cu/D composites increased their wear resistance.
Corrosion also attacks the path that runs along the grain boundaries.

One important category of diamond tools is diamond tools having only monolayer of diamond grains, which are usually fabricated by electroplating.
However electroplated diamond tools have some critical problems, such as small holding space to chips and low joining strength between the grains and metal matrix, and thus the diamond grains are easy to pulled out and the tool gets failure too early during grinding, which has been one of the most important reasons to restrict the broader application in modern machining industry [1].
The grains, the brazing alloy and the substrate of this kind of grinding tools could join hard together through the chemical reaction.
Reseaus are carved up with transition element, for reducing the element number and increasing calculative speed.
Very obvious, the wetting of Ni-Cr alloy to diamond is good, there could be any reactions between the Ni-Cr alloy and the diamond grain.

The high treatment temperature contributes to recrystallization and grain growth.
The microstructures of samples treated in 700~1000°C show a large number of σ phase (in Fig.2).
When solution treatment temperature is 900°C, more σ phase is mainly precipitated in the α/γ grain boundary, as a hard and brittle phase.
When the tensile load applies to the sample, σ phase causes grain boundary embrittlement, resulting in intercrystalline fracture and decrease of the extension rate[8].
(3) The σ phase causes grain boundary embrittlement, resulting in intererystalline fracture after treatment at 900°C, and ductile fracture after treatment at 1050°C.

A number of polymer superconducting ceramic compositions using thermoplastic and reactoplastic polymeric matrices are described in the literature [5-7].
With regard to conventional fillers, the free oxygen dislocated on the surface of the ceramic grains of the high Tc superconductor, will have a significant impact on the formation of a phase boundary, the physical–mechanical properties, and on the SC properties of the polymer–ceramic composites.
The Bi-2212 grain boundaries were not clearly seen on the SEM micrographs.
The morphology of the composite clearly shows the excellent wetting and proper filling of the voids between the polymer and the superconducting grains.
A short gap between Tc & T0 indicates that there is good grain connectivity and also low resistance between the surface of the coupled grains [12, 13].

Based on the researches about mechanical properties of ceramic materials, a number of approaches to improve the strength and toughness of ceramic materials have developed.
The particle reinforced ceramic composites described constitute perhaps the simplest departure from a fine-grained single-phase ceramic.
This is especially serious in the data base for the fundamental parameters such as the surface and grain boundary energies and the diffusion coefficients.
At this stage, the grains in particles do not change, the basic shape of particles remains unchanged, and there is no shrinkage in the matrix, the density increased so little.
In reality, however, the similar shape assumption is generally not satisfied in sintering of powder compacts because the mechanism of grain growth is, in general, different to the mechanism of densification.

For comparison with the thicknesses calculated from the sheet resistance values, a number of samples were selected for thickness measurement using Rutherford backscattering spectrometry (RBS).
Grain size was assessed using transmission electron microscopy (TEM).
The morphology and grain size as observed by TEM for the as-deposited and annealed Ru films are shown in Figure 2.
The significant increase in the grain size of the Ru layer caused by the anneal at elevated temperature could partially explain the slow etching behavior of this film.
Figure 2: Morphology and grain size obtained with TEM for (a) as-deposited and (b) 420 ºC-annealed Ru.