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Grout can transport every grain of aggregate, which allows for the migration of grains in relation to other grains.
Series number 3, containing 40% of recycled cement obtained body density rate by 9% lower than series number 1 and 2.
The gross density of the selected series of the fine- grained samples was examined.
The results of the porosity of concrete maturing for 28 days under the laboratory conditions Series 1 8.07 The porosity of the fine - grained concrete [%] Series 2 9.05 Series 3 15.17 The lowest porosity of 8.07 % was obtained by series number 1, which did not contain any recycled cement. 20% addition of recycled cement resulted in a slight increase of porosity, while the highest porosity rate of 15.17% was obtained by series number 3 which contained 40 % of recycled cement.
The study variance was N = 12 , while the number of repetitions n = 3.

The paper focused on analysis of local texture changes, particularly at the boundary between grains.
The shear grain is decomposed by lattice rotation in contrary directions.
(b) The pole figure magnification with marked element numbers and groups of rotation.
(c) Scheme showing finite element mesh with assigned element numbers and group of orientations.
In Fig. 6 the orientations of elements with shear orientation at grain boundary are presented.

In grain A, fine cracks and small cleavage steps existed, the cracks were propagated from grain A to grain B, altered the propagation direction at the hindrance of grain boundary, and finally led to increase the steps height in grain B.
The fracture was serrated and the number of mechanical twins in grains at −196 °C was less than at 25 °C.
The low temperature plasticity at −196 °C may have relation to the activation of new slip systems which suppress the occurrence of twinning, because the number of twins at −196 °C was obviously less than at 25 °C(see Fig. 4(a)).
The twinning can easily occur in the pyramidal planes }1110{ or 1}2{11 at beginning of plastic deformation, so that the number of twins at 250°C is the most in the six tensile temperatures, and when the deformation temperature is enhanced to 300 °C or 350 °C and the number of twins decreases or even to zero.
Due to the strength of the interior grain at 400 °C is higher than that of its grain boundary, the deformation can not reach interior grain easily by slip, but the stress can induce the nucleation of twinning on grain boundaries and the twinning further extends to interior grains.

With the increase of dressing depth, surface peak and valley values of elliptical ultrasonic vibration dressing grinding wheel increases, while the number of static effective abrasive grain reduces.
(a) Elliptical vibration amplitude transformer (b) Dressing System Fig. 1 Test Tooling a Longitudinal vibration feature b Transverse vibration feature c Synthesis of vibrations Fig. 2 The Elliptical Vibration Measurements Dressing Conditions:To distinguish between resin bonded diamond grinding wheels and metal bonded diamond grinding wheels, R and M is added respectively before the corresponding size number as prefix, such as, R100 refers to resin bonded diamond wheel with the grain size of No. 100, MW10 refers to metal bonded diamond grinding wheel with the grain size of No.
With increase of dressing depth , the surface peak and valley values of elliptical ultrasonic vibration dressing wheel increase, that is the protrusion height of abrasive grain increases, while the number of static effective abrasive reduces; ordinary dressing grinding wheel surface has a similar variation feature, but the number of static effective abrasive reduces faster and abrasive distribution is more irregular.
With the increase in dressing depth, the surface peak and valley values of elliptical ultrasonic vibration dressing wheel increase, that is the protrusion height of abrasive grain increases, while the number of static effective abrasive reduces; ordinary dressing grinding wheel surface has a similar variation feature, but the number of static effective abrasive reduced faster, and the abrasive distribution is more irregular.
The number of static effective abrasive is larger, while the protrusion height is higher and abrasive accordance gets better.

The size effect occur in thin metal foils because of low number of grain.
The surface roughening in coarse grain, increased higher than in fine grain.
The inhomogeneous grain strength in coarse grain is higher than fine grain in SUS 304 thin metal foil.
Conclusion In SUS 304 thin metal foil, the Ra increases higher for coarse grain than fine grain, because of the lower slip band intersection in coarse grain that affect to lower MPT in coarse grain, compared to fine grain.
In SUS 316 thin metal foil, the Ra increase higher for coarse grain compared to fine grain, because of GMO lower in coarse grain compared to fine grain that affect to more inhomogeneous grain strength in coarse grain compared to fine grain.

A number of studies have been initiated in recent years that examine the tribological and wear performance of usual silicon nitride materials with several micrometer grain size in a variety of wear environments.
Relative density and grain size.
Although the average grain size was very small at 1500˚C, the density was only 86%.
The average grain size was less than 500nm at the sintering temperature below 1700˚C.
The average grain size of sintered body is less than 500nm.

Their room temperature tensile properties were examined and compared to those of coarse grained counterpart.
Introduction The advent of innovative severe plastic deformation (SPD) techniques makes the grain size of metallic materials be easily refined to the submicrometer level, so-called ultrafine grained (UFG) materials.
UFG materials are quite attractive due to their ultrahigh strength, more than twice of the coarse grained counterparts.
Both ferrite grain size and martensite island size were ~1.3 µm and the martensite volume fraction was about 28 %.
The microstructure of the ECAPed low carbon steel is characterized by UFG ferrite grains with a high density of lattice dislocations, subdivided pearlite colonies, and a large number of low- and high-angle boundaries with extrinsic boundary dislocation, etc [8].

Compared with the high heating rate treatment, the slow one apparently leads to significantly smaller Al3Zr dispersoids, the dimension of the dispersoids decreases from 35 nm to 22 nm, and the number density of Al3Zr particle in the center of the grains increases from 13/μm2 to 35/μm2.
A large number of non-equilibrium constituent phases are present along primary α-Al grain boundaries in the ingot.
These Al3Zr particles are to stabilize the grain structure of the alloy and prevent recrystallization after hot deformation by pinning grain and subgrain boundaries [7].
There are no dispersoids precipitated adjacent to the grain boundary in two nearby grains, while in the other grain the Al3Zr particles are dispersly distributed.
Thus, a larger number of dispersoids can be formed by holding at 400°C.

Therefore, when the grain size of a polycrystalline aggregate is reduced, the fraction of atoms at structurally disordered sites increases while the number of atoms at perfect lattice sites decreases.
However, this number can be substantially increased to over 80% in what is referred to as grain boundary engineering.
It should be noted that the value of 0.48 B for site 1 does not significantly reduce the total moments associated with the 5 boundary, since Ni (1) sites constitute only a small portion of the total number of atoms in this boundary.
Note that the hardness values in this figure are given in units of Vickers Hardness Numbers (VHN).
The Taber wear index is usually given as a unitless number: the lower the Taber wear index the higher the material's resistance to abrasive wear.

It focuses on the measurement of sulphur grain boundary segregation in nickel on fractured surfaces.
Analysis of sulphur grain boundary segregation on a nickel fracture surface by EPMA-WDS.
Sulphur grain boundary segregation kinetics at 750°C Figure 6.
Sulphur grain boundary segregation at 750°C measured by EPMA-WDS.
McLean: Grain Boundaries in Metals.