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This area is separated from the base material via a fine-grained layer.
Here solidification rate was high enough and a large number of crystal nuclei were available, so grain growth was stopped before dendritic growth could start.
In the last clad layer, the average grain size is fine, due to rapid cooling.
It can be distinguished between c) the middle of the prismatic structure with grain size 5.1 µm and d) the top of prismatic structure with grain size 5.6 µm.
A fine grained microstructure with an average grain size of ~5-6 µm was formed in the prismatic structure.

A larger grain medium-porosity B91-150V1 CBN wheel is identified by the notation MP-B91.
For the same concentration, the grain density for the HP-B64 wheel should be nearly 3 times that of the MP-B91 wheel, and the grain density for the HP-B91 and the MP-B91 wheels should be the same.
With the high-porosity fine-grain HP-B64 wheel, the power was lower than for the medium-porosity medium-grain MP-B91 wheel.
The larger spacing leads to a larger mean uncut chip thickness and a larger grain depth of penetration.
Higher wheelspeed reduces grain depth of penetration, which leads to lower grinding force on each cutting edge.

There was δ ferrite scattered on austenite grain boundary.
Weld zone also got different grain shape to base material during weld melting and rapid cooling process.
Grain size number of TP347H was 7, and its solution treatment micro-structure was austenite and few carbide.
Because these tiny second-phase particles (carbides, nitrides of Nb and Cu wealthy phases) could resist growth process of austenite grain, Super 304H has finer crystalline grain than TP347H.
Corrosion resistant capability of metals was mainly related to their component, microstructure and grain size.

Cr, which is adjacent to Mn in atomic number, is also a transition metal element, with more multiple valence state from +2 to +6.
Their average grain size is 375 nm and 400 nm, respectively.
It can be considered that Cr2O3 dopant is incorporated into the perovskite grains or coated on the surface layer of grains.No band peaking at 863 cm-1 was observed in C61 and C62.
This fact implies that only a small amount of Cr4+ ions are incorporated into the perovskite grains or coated on the surface layer of grains when CrO3 dopant was adopted.
Cr5+ exists in the surface layer of grains because the 863 cm-1 band associated with incorporation of Cr5+ (or Cr3+) into the lattice of grains was not observed.

The material were nano-composite ceramics of Al2O3-ZrO2 and fine grain ceramics of ZrO2.Matrix phase and reinforced phase were scattered in different electrolytes, then the medium parameters of disperse phase solution such as the pH value and the ratio of electrolyte concentration to the number of the two particles were regulated properly to make the particles of two phases charge inversely.
The surface residual stress in OG became greater with the larger grain size.
The surface residual stress using grain size of 270# was 37Mpa in TDUVG, smaller than that using fine grain size.
Residual compression stress decreased with the grain size.
The smaller the grain size is, the less the tensile stress is.

And a number of Al-air batteries have been previously reported [4, 5].
A lot of dendritic structure and element enrichment on the grain boundaries can be observed in Fig. 1a.
In the sample with 80% cold rolling reduction, the wider and curved grain boundaries were observed.
At the same time, the grain elongation was found at the grain boundaries (Fig. 1d).
The dendritic structures in alloy was broken into smaller particles, smaller grains will increase its area of grain boundary so as to the grain boundary attenuate, In addition, the precipitates distribution in alloy became more uniform, they led to the lower grain loss caused by the micro-cells.

Grain sizes were determined by using ImageJ software from SEM photos.
The Fourier transformed infra-red (IR) spectra were recorded using IRPrestige-21 in the 400 – 4000 cm-1 wave number range by the KBr method.
Results and Discussion Densification and Grain Growth.
Generally, during sintering grain size of samples changes or grain growth occurs.
The solid line is an fitting of grain size data.

The polished samples were etched in cold nitric acid (~ 0 °C) for 1 minute to reveal grain structures.
Overall, the two materials appeared to have similar grain sizes, resulting in similar yield strengths.
On the other hand, after 8 passes, all grains were deformed and refined [14, 15] and the material had a uniform fine grain structure.
The different behaviours may be attributed to the nonuniform grain size distribution in the material after 4 passes.
Fig. 6 TEM bright-field image showing refined grains in the Mg material after BP-ECAC for 4 passes at 200ºC.

The HCF-regime is described by a gradient of k = −0.373 up to a number of cycles of n = 2×106 at a load of σ = 100 MPa.
Nonetheless, due to a strongly flattened curve, an improvement of the performed numbers of cycles can be found from an amplitude of σ = 500 MPa, expanding during the HCF-regime, as the VHCF is accomplished at a load of σ = 200 MPa with a number of cycles of n = 1.8 × 106.
For the as-built state, a very fine-grained material texture develops due to the high cooling rates during PBF-LB/M.
A grain boundary migration is prevented, as well as the Laves phase precipitates at the boundaries, solidifying a fine-grained microstructure with irregular grain boundaries [6].
Contrary, the additionally performed solution treatment leads to a more homogenised material structure, as a grain growth is developing, forming columnar grains [4].

It can be seen from Fig. 3 and Fig. 4 that there are many protuberances on the finished surface which are crystalline grains of glass ceramic.
The crystalline grains are evenly distributed on the surfaces which are the fundamental compositions of glass ceramic.
As the crystalline grains are harder than the glass phase, the finishing process removs more glass phase from the workpiece surface.
The residual crystalline grains extrude and make the surface seem uneven.
Digital Instruments NanoScope Scan size 5.000µm Scan rate 1.489Hz Number of samples 512 Image Data Height Data scale 35.25nm X 1.000µm/div Z 35.246 nm/div