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A competitive formation of precipitation is influenced by either initial grain size or applied cold deformation before ageing.
DP forms behind a moving high angle grain boundary and ‌its nucleation depends on the diffusion along a moving grain boundary and a thermodynamic driving force.
Experimental The commercial die cast alloys AZ80 (Mg-8.2Al-0.5Zn) with the average grain sizes about 250 and 750 μm were supplied by Timminco Inc.
One part of the solid solution treated (SST) samples with coarse grain size was deformed by cold rolling.
This process is more expressed in the GRSST alloy because of a higher number of grain boundaries.

In the examination of the blasted surface the value of roughness is given mainly by the size and imprints of the blasted device grains.
The size of tracks after the incidence of the blasted device grains primarily depends on the dimension and a kinetic energy of grain, its temper as well as on the hardness of the basic material [1,2].
The shape of grain of utilized blasting device – rounded or sharp-edged, has its influence on the character of the blasted surface micro-geometry.
In the case of blasting by sharp-edged grains of blasting device – the grit; a relief with the number of sharp notches in a material is created.
The number value states the strength of relation and a number sign sets direct or indirect relation.

A large number of macro-cracks were observed on the side wall and at the bottom of the crater.
In addition, a large number of holes and cracks could be seen on the inner wall surface.
The grain generated slight plastic deformation, as is shown in in Fig. 5(c).
Finally, the fine equiaxial grains formed, as is shown in Fig. 6(b).
A large number of micro-voids were observed in the shear bands, as is shown in Fig. 7(a).

The extended volume concept is used to deal with grain impingement.
When equiaxed grain envelopes fully occupy a CV (equiaxed grain fraction=1.0), columnar growth is halted locally and no further growth of the columnar front is allowed.
But, such grains are elongated until a distance of 1314cm.
Therefore, the number of the uniformly distributed seed particles was increased to 750, which gives the close match for grain size of reported experimental results [5].
This deterministic model predicts the columnar and equiaxed grain fractions with average equiaxed grain size.

The interface of inclusions is the trap of hydrogen, is the birthplace of crack, the more the number and size of the inclusion, the greater of the sensitivity to the SSCC and HIC.
The application of full flow high clean smelting and thermo mechanical control process (TMCP) technology to realize the depth of desulfurization, dephosphorization and modification of inclusions, effectively controlled the number of inclusions and forms, made the raw steel purity and refine grain.
The structure is mainly consisted by Ferrite, the hardness is ≤18HRC(230HV), grain size ＞11grade, inclusion is less than 1.0 grade, band structure is in the range of 0.5-1.0 grade.
As the demonstration in the Fig. 2 (a), 2(b), the main structure of CT80S is ferrite and pearlite; the structure is uniform; the raw material grain size is 12 grades, conforms to the API Spec 5ST standard requires grain size 8 or more than 8; banded structure is 0.5 grades and the inclusions are less than 1.0 grades.
As the research, the number of fatigue cycle is related with the size, yield grade and operation pressure etc[18-19].

They demonstrated that the application of a higher number of deposited layers did not substantially increase their anticorrosive properties.
The structure involving small grains and crystalline materials.
The nano-structures, composing of nano-particles, generate large number of internal interfaces in the liquid matrix causing the formation of small grains.
This, in turn, results in large number of interfaces in the liquid matrix while suppressing the grain growth in this region.
This is because of the grain refinement in the coating.

Ultrasonic techniques are an established means for carrying out fatigue tests at very high numbers of cycles.
Generally, higher stress levels of σm and/or σa lead to lower numbers of cycles until failure Nf.
Some regions of the fracture surface showed striated, delaminated grains without dimples (f), suggesting that not only grain boundaries, but also the bulk of grains were embrittled during exposure to GH2.
The rest of the fracture featured more flat grains mixed with some dimples (c).
The grains revealed striation bands (c) and very sharp edges.

There was no significant difference among the reducing power of six different purple corn grain extracts.
In this investigation, purple corn hybrid grains were dried and grounded before extraction.
Fig.1 Reducing power of six different purple corn grain extracts.
Fig.2 Superoxide radical scavenging activity of six different purple corn grain extracts.
This may depend on the position and number of hydrogen donating hydroxyl groups on the aromatic cycles of phenolics molecules [24].

Only grains elongated along RD are observed while no recrystallised grains occur in the deformed state.
Below Tc: the larger grain size and smaller number of grains indicates a lower frequency of nucleation and grain growth with migration of high angle grain boundaries.
On the other hand, grain growth occurs by large angle grain boundary migration.
It has been reported that the activation energy for low angle grain boundaries migration has a significantly larger value than that for high angle grain boundaries migration [10, 11].
Vol. 18 (1970), p. 639 Journal Title and Volume Number (to be inserted by the publisher) 7 [11] E.

SEM micrographs also suggested that the morphologies of doped CCTO ceramics had showed a matrix consisting of large grains wherein the small grains were embedded between the larger grains.
Doping can increase or decrease the growth of grain [1].
Interfaces between grains have mixed morphology with flat and curved.
The micrographs show a few exaggerated grains of size 1-3 mm in a matrix containing grains in the size range 5-10 mm.
The morphology of the undoped specimen consists of some huge grains, surrounded by small ones.