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Under this growth condition, it is conducive to form integrated tips because deposited diamond grain sizes can reach several microns.
This [011] diffraction pattern also shows perfect face-centered cubic (fcc) crystal structure of original C2000 grain.
All twins are aligned along the same direction and grain boundaries are absent.
However, thickening of the twin would not increase the number of twin boundary.
Lu, Strengthening an Austenitic Fe-Mn Steel Using Nanotwinned Austenitic Grains, Acta Mater. 60 (2012) 4027-4040

With the increase of N2 flux, a large number of N atoms gathered around the grain boundary, so that thin film tended to be amorphous structure gradually, and the micro-hardness began to lower slowly.
Substrate temperature affected the crystal grains' growth.
When the substrate temperature was low, the film was porous, and TiN nucleation was not fully, the crystal grains were coarsened.
All the TiN films were dense and leveling, the grains distributed uniform.
But when the temperature was 100°C and 200°C, the average grain size was large, when the temperature was over 300°C, the average grain size tended to be fine.

The microstructures of the hot deformed alloys are typical of fine equiaxed Al grains with uniformly distributed fine Si particles.
The common microstructure feature, i.e., fine equiaxed Al grains and uniform distributed Si particles among Al grains, observed in hypoeutectic, eutectic and hypereutectic alloys, suggests that the mechanisms contributable to the microstructure evolutions during hot deformation are the same.
In Fig. 6, the white gray particles are Si and the rest is Al matrix; the dark lines represent the high angle grain boundaries (GB) of Al matrix.
It can be seen that when the amount of deformation is low, the distribution of Si particles in the matrix is uneven, and the number of Al grains with high angle GB is low either.
Ruano, Particle and grain growth in an Al-Si alloy during high-pressure torsion, Scr.

The high grain protrusion and the very low amount of bonding material (except of the identical nickel-plating) permitted the comparison of diamond and cBN grain as cutting materials, with a minimum influence of the bonding system.
Afterwards, a comparison of different bonding systems (electroplating, vitrified and resin bonding) for the selected grain type took place.
The investigation of single grain wear using scanning electron microscopy showed no significant differences for diamond and cBN grain for when grinding with electroplated bonding [9].
The experiment was repeated using tools with average grain sizes of dkg = 126 µm and dkg = 181 µm showing a similar behaviour.
Further improvements can be achieved by high feed angles and low widths of cut that lead to higher overlaps of the single grain paths on the ground surfaces.

The BM microstructure of the HSLA-80 steel is ferritic consisting predominately of polygonal (idiomorphic or intragranular) ferrite (αp) that had roughly equiaxed grains with smooth boundaries and quasi-polygonal ferrite (αq) with undulating grain boundaries, some of which possibly originating from grain boundary (allotrimorphic) ferrite.
Typical microstructures are present in Fig. 2 for the sub-regions of the HAZ, i.e. intercritical HAZ (ICHAZ), fine-grained HAZ (FGHAZ), and coarse-grained HAZ (CGHAZ).
In CGHAZ, γ grain growth usually occurs at peak temperatures > 1100°C for HSLA-80 steel due to the dissolution of Nb(CN) precipitates, which otherwise pin the γ grain boundaries and delay the γ-to-α transformation [8].
Grain refinement is due to the large number of nucleation sites provided by the α grains at the time of heating.
In the lower section of the Y-groove, equiaxed prior-γ grains were observed.

The main features of chemical composition of tested X80 pipeline steel are low C, low P and ultra-low S, and there are a small number of Mo and high Nb in it.
When cooling rate reaches 10℃/s, there are evident features of acicular ferrite which appears irregular un-equiaxed and has blurring grain boundaries, uneven grains and no whole continuous boundaries.
Fine M/A islands distribute among grains or inside, and indistinct embossments and sub-grain stripes emerge in acicular-ferrite, and there are high-density dislocation inside, which prevents the grain from growing and makes the grains finer; when cooling rate is 40℃/s, indistinct initial austenite appears and there are obvious bainite-ferrite slabs whose distribution is chaotic and the orientation relationship is not sure.
From the property point of view, in spite of the sub-grain strengthening, dislocation strengthening and fine-grain strengthening of bainite-ferrite which are beneficial for strength and toughness, as to the microstructure, size of the slabs and different length-width ratios would result in major differences in property [7, 8].
It is shown by comparing dynamic CCT microstructure under different cooling rate (Fig. 2) that as cooling rate increases, the grains become finer.

It can be found that no matter with coarse or fine abrasive grains, surface roughness Ra will increase with the increase of feed rate.
Besides, the decrease of particle number in unit length on the workpiece with the increase of feed rate, which causes the increase of single particle load, is also a reason for the increase of surface roughness.
But the mutual effects of abrasive grains will be gradually weakened with the increase of feed rate.
This is because the increase of ultrasonic amplitude causes the increase of vibration velocity and vibration acceleration of abrasive grain and the uniform of the depth scratched by grains in workpiece, which cause the reduce of surface roughness.
Apart from this, the surface roughness also lies on the grain size of ceramic material.

(a) loading perpendicular to the grain (b) loading parallel to the grain Fig. 2.
(a) perpendicular to grain loading (b) parallel to grain loading Fig. 3.
Monotonic curves of T shape nail connections (a) perpendicular to grain loading (b) parallel to grain loading Fig. 4.
(a) perpendicular to grain loading (b) parallel to grain loading Fig. 5.
Hysteresis curve and average monotonic curve of T shape nail connections (a) perpendicular to grain loading (b) parallel to grain loading Fig. 6.

The high temperature mechanical properties, especially creep, of silicon nitride depend on the types and amounts of sintering additives used which determine the volume and chemistry of the grain boundary glasses [2-4, 6-7].
A number of studies [5, 8-13] on oxynitride glass formation, structure and properties have shown that oxynitride glasses exhibit higher glass transition temperatures, elastic moduli, viscosities and values of hardness compared with the equivalent silicate glasses due to extra cross-linking within the glass network as a result of substitution of oxygen by nitrogen.
This paper outlines the effect of compositional changes, especially nitrogen content, on properties of oxynitride glasses, such as glass transition temperature and viscosity, and discusses the implications for high temperature behaviour of silicon nitride ceramics. ______ (a) (b) 10nm Figure 1: (a) Scanning electron micrograph of silicon nitride sintered with yttria and alumina showing grain boundary glass phase (white), (b) transmission electron micrograph showing glass film between two silicon nitride grains and at triple point.
Overall, these effects can be assumed to be related to changes in the density of the glass network and the numbers of non-bridging oxygens as Al changes from a network ion (AlO4) to a modifying role (AlO6). groups can accommodate more modifiers in "charge accommodating" sites than the equivalent oxide glasses.
Modification of the sintering additives results in changes in the composition of the grain boundary glass phases in silicon nitride.

Addition of scandium can improve significantly stress corrosion cracking of the Al-Zn-Mg-Cu alloys aged on the maximum durability. [6] In a number of works positive influence of scandium on mechanical characteristics of aluminum alloys of different systems of alloying is shown [7-10].
Result and discussion From a number of references there is information on decrease in grain size in ingots and the deformed semi-finished products of aluminum alloys of different alloying systems. [13] For the purpose of establishment of effect of this additive together with zirconium and manganese microscopic researches have been carried out.
Apparently from comparison of microstructures (fig. 1) after solution treatment alloying with Mn and Zr provides fine grain microstructure with average grain size in the direction of rolling of 40 microns, nevertheless alloying with small additive of scandium allows to suppress almost completely recrystallization processes, at big increases it is possible to notice only small high-angular borders of grains.
From results of tests (table 2) it is visible that the additive of scandium does not influence intergranular corrosion resistance, thus, somewhat reduces the resistance of exfoliation that, may be connected with preferable structure in the sheets containing scandium and un-recrystallized grains.