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This movement is prevented by obstacles such as grain boundaries, particles as well as by dislocations and their accumulation, which leads to work hardening of the material.
An increase in strength can be achieved by increasing the martensite volume fraction or by grain refinement [13].
For this reason, it is assumed that the DH800 has a coarser-grained structure with lower martensite content, whereas the DP1200LY has a finer-grained structure with higher martensite content.
According to this, an increased ferrite volume fraction is associated with a higher number of mobile dislocations, which potentially increase in microplastic strain due to their elastic recovery.
In this case, the initial microstructure of DP1200LY, characterized by a higher initial dislocation density in the martensite phases, the ferrite phases near grain and phase boundaries as well as an increased pinning of mobile dislocations due to the fine-grained microstructure might explain this behaviour.

The lattice direction ratio for a NbN coating changes as the number of nitrogen vacancies changes for various preparation conditions.
TiNb-N4 has the largest surface grains, as shown in Fig. 2 (a).
The surface becomes denser and dense, uniform grains are observed on the surface of TiNb-N16 (Fig. 2(d)).
The most superficial NbN coating has fine, dense and more uniform grains.
The multilayer coatings are deposited alternately so grain growth in NbN and TiN is interrupted and the grains are smaller than those for a single-layer coating [26].

Strengthening of the graphene MMC relies upon the handling strategy, interface quality, scattering at grain limits, and their natural qualities, for example, grain size, perspective proportion, and calculation.
Even then the Graphene particles will form into mass at certain value that leads to mechanical deterioration which is required to be optimized number of additives [3,20].
Grain Refinement: Here with the reference the of Fadavi Boostani et al [3,21].
The growth of the Al grain while in the process of fabrication affects movement of dislocation due to its adjacent grain in enhancement for of strength.
It shows uniform distribution of composition in 1% of Gr and common defects arises due to their grain size increases in graphene properties.

Introduction A number of Ni-based superalloys currently in use are composed of a two-phase microstructure consisting of γ (Ni solid solution (A1 phase)) and γ' (Ni3Al(L12 phase)).
Also, it is likely that the recrystallized grains appeared at 1223K.
This means that grain boundaries contributed to the strengthening at low temperature, but to the softening at high temperature.
One reason for this feature is that the number of dislocations piled-up Fig. 9.
Also, Fig. 9(b) clearly indicates that the grain boundaries deteriorate the tensile ductility of the dual multi-phase microstructure.

A number of topics were highlighted in the scope of special sessions and some of the presented  papers are collected in this volume: FLOW SYSTEMS, DESIGN AND OPTIMIZATION (SS1) (by A.F. 
Belova), GRAIN BOUNDARIES AND INTERFACES: STRUCTURE,  THERMODYNAMICS AND DIFFUSION PROPERTIES (SS3) (by V.V. 
The large number of presented papers emphasises the considerable academic and  industrial interest in the conference theme. 

This paper deals with the possibilities of experimental determination of the dynamic and static modulus of elasticity of fine-grained cement composites in the early stage of setting and hardening - up to 72 hours.
However, to thoroughly understand the process of shrinkage, the knowledge of chemical and physicochemical processes is not sufficient and a number of other characteristics relating not only to concrete but in particular to simpler composites – basic cement pastes and cement mortars, has to be taken into account.
Standardized silica sand CEN-196-1 with a 02 mm grain size was used in the production of the cement mortars.
It is primarily used to determine the duration of setting and hardening of cement mortars as an alternative to Vicat's apparatus, but can also be used on coarse-grained materials.

Despite the large number of other non and semi-destructive technique developed their regular application to in situ assessment of timber’s mechanical properties is still almost non-existent.
After removal of pieces rejected for structural applications (not fulfilling grade E) the number of pieces graded as C14 are 0%.
VSG standards are based on independent variables (e.g. knot size, rate of growth, slope of the grain) showing a weak correlation with the different reference properties.
For that purpose it can be used small wood samples for performing tension or compression testing parallel to the grain [2, 17].
Machado, Chestnut wood in compression perpendicular to the grain: Non-destructive correlations for test results in new and old wood, Construction and Building Materials 21 (2007) 1617-1627

This process is accompanied by acoustic emission (AE), which develops as the number and size of cracks grow, as well as the formation of destructive zones.
Calcite samples were taken from marble, which measured (8.0×2.0×2.0)×10-6 m3 and had the structures: coarse with grains (3-6)×10-3 m, fine structure with grains (1-3)×10-3 m.
Samples consisted of ×coarse marble with a grain size of 3-6 mm and fine marble with a grain size of 1-3 mm, as well as stalactite, which has a sinter structure.
It is known that the polarization magnitude depends on the grain size [19, 20].
At the same time, the amplitude of the electromagnetic response to external acoustic excitation from coarse-grained marble is higher than that of fine-grained marble.

In a planetary mill, it is reasonable to consider that the total number of collisions is directly related to the number of revolutions.
Therefore, by plotting data as a function of the product of the number of revolutions and the number of grinding spheres (x-axis), distinct grinding conditions may be normalized.
Microhardness evolution as a function of the number of collisions.
A similar observation has been made by Schaffer e McCormick [7], who varied the number and size of spheres.
It is understood that this effect is related to the incorporation of defects in the Zr lattice, as demonstrated indirectly by the increase in microhardness of powder particles during MA, as well as by the reduction in average grain size, resulting in an increased grain stress [10], which seems to be deleterious to hydrogen absorption.

Be three in number (at minimum).
Grain size is observed to have inverse relation with percenatge Co content.
Average grain size of Zr47.5Cu45.5Al5Co2 is 6μm.
The addition of Al and Co significantly refines the grains.
Rappax, Analytical and numerical predictions of dendritic grain envelopes.