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Viscosity Flow abrasive is two-phase flow, namely abrasive contains fluid medium and little flow additive, also contain numbers of solid grain, as shown in Fig.1.
When abrasive is static or uniform motion in a straight line, the velocity of grain is same as abrasive.
When grain cutting workpiece, the medium and grain condition has been separated to analyze, analyzing the force from flow medium to grain.
When m is equal to 1, abrasive is Newtonian fluid. μ is not a constant value, which is depended on various elements such as grain size, medium character, temperature, pressure, the proportion of grain and medium.
In the present work, abrasive consists of numbers of grains (SiC), some medium (silly putty) and little lubricant (silicon oil).

The value j controls the number of preferential growth directions.
A usual expression for this noise, as indicated by Ferreira and Olivé [4] is noise=16arϕ2(1-ϕ)2 (8) with r a random number between -1 and +1.
The advanced columnar grains in Fig. 1(a) grow preferably; grains stop advancing or slightly melt back, Fig. 1(b).
After the selection of the columnar grains, the coarsening of the selected grains is observed in Fig.1(c).
The competitive growth of grains becomes less intensive with the advance of the columnar grains into the liquid region.

The grain average sizes are listed in Table 2.
For the content of Sc was 0.25%, less than 0.55%, the grain of Al-0.25%Sc alloy was not refined, remaining the columnar grains.
Ti is claimed to be a kind of excellent grain-refining element.
When 0.03%Ti was added to the Al-0.25%Sc alloy, a small number of Ti can partially substitute of Sc forming Al3(ScxTi1-x), which is coherent with matrix and has a misfit of 1.33% and other Ti in matrix can refine grain through constitutional supercooling and growth restriction, so grains of the Al-0.25%Sc-0.03%Ti alloy are much finer than those of the Al-0.25%Sc alloy.
The Al-0.25%Sc-0.2%Zr-0.03%Ti alloy has the finest grain.

The grain boundaries are decrease with the increase in concentration of TiO2.
Solid state sample is represented by the very loosely formed by defined grains.
A small number of spherical macro pores is observed.
The COP sample is having agglomerates of fine grain particle while SSR sample is having larger grain.
This is that making coprecipitation produce denser sample with finer grain comparing solid state reaction which is larger grain throughout all weight percent addition of TiO2.

The ceramic gas nozzle of the CGAW torch used was number 4 with a hole diameter of 6.4 mm [21].
In both cases, a fine-grained region was observed along the welding line, followed by coarser grains in the melting spot area.
In contrast, the Type 100 sample had significant differences in grain size, namely, the vortex areas contained very fine grains, while the grain size of the copper matrix surrounding the steel globules was about 15 μm (Fig. 8c).
The heat-affected zone (HAZ) of the copper side in both samples was divided into two regions: HAZ with fine grain (FHAZ) and HAZ with coarse grain (CHAZ).
Heliyon, 9(11), (2023) Article number e21529. https://doi.org/10.1016/j.heliyon.2023.e21529 [12] A.

Because of the intrinsic capability of the perovskite structure to host ions of different sizes, a large number of different dopants can be accommodated in the BaTiO3 lattice [1,2].
The tolerance factors tA and tB for the rare-earths 3+ ions R 3+ are presented in Fig. 1 as functions of the ionic radius r(R 3+VI) where the suffix represents the coordination number.
The previous studies suggested that the grain growth of Dy-doped BaTiO3 was restrained during sintering.
In contrast, coarsed-grained structure (see Fig. 6(a)) of sample doped with 0.3mol% Dy showed semiconducting behaviour.
In contrast, the sample doped with 0.3mol% Dy with coarse-grained structure showed semiconducting behaviour.

As all we know that the ingot has numbers of eutectic phases and dendritic segregation.
Severe dendritic segregation can be found in the ingot, and a considerable number of secondary phases exist at the grain boundaries.
In addition, the grain boundaries become thinner and clearer with the temperature increasing, and the residual phase distribution along the grain boundaries develops a discontinuous pattern.
When the temperature is increased to 510℃, the residual phases in the grain boundaries decrease significantly.
Grain boundary corrosion and stress corrosion cracking studies of Al-Li-Cu alloy AF/C458 [J].

A number of techniques have been developed to improve the processing to achieve high critical current densities Jc.
A number of practical applications would benefit from the possibility of employing a MgB2 conductor to realize DC windings that can be operated in persistent mode.
JC vs B improvement by MgB2 powder control One of the advantages of the ex-situ method is the possibility to control the properties of the MgB2 powders as grain size, purity, grain boundaries and crystalline stress.
In particular we have worked on the reduction of grain size by milling the powders.
The pinning force behavior is well described by grain boundary based pinning model, suggesting that the ball milling process increases the number of grain boundaries lowering the average grain size without any addition of lattice strain -0,1 0,0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1,0 1,1 1,2 1,3 0,0 0,2 0,4 0,6 0,8 1,0 b1/2 (1-b) 2GBs pinning model H / H*K F / FPmax T = 5 K not milled Increased milling time -0,1 0,0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1,0 1,1 1,2 1,3 0,0 0,2 0,4 0,6 0,8 1,0 b1/2 (1-b) 2GBs pinning model H / H*K F / FPmax T = 5 K not milled Increased milling time Fig. 9: Behavior of the normalized pinning force vs normalized magnetic field: a comparison with grain boundary pinning model is also reported.

Grain refining, with master alloy AlTi5B1, was performed in the crucible prior to casting.
The sand moulds were produced in a core shooter to ensure a consistent mould quality, and a fast production of a large number of moulds.
Grain coalescence occurs earlier for alloy A compared to alloy B.
From grain coalescence onwards, the alloys rapidly build strength.
· Grain coalescence for alloy A occurs at fs~0.95 and for alloy B at fs~0.98

The size, shape and numbers of the pores can be adjusted by the added filler.
It can be seen that both the surfaces are highly compacted and a few number of pores can be found.
These pores provide large space for chips and make the fresh grains emerge easily.
It also can be seen that the number of pores on tool surface after 6 h lapping tends towards decrease.
Bond fracture refers to dislodge of the abrasive grain from the binder [9].