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In the HAZ near FZ an important grain growth due to the heating occurred.
Also, close FZ that was submitted to new heating due to repair it was noted an apparent growing of grain size relative to original grain size.
An 8-9 grain size (~ 16 μm) was found under the ASTM E112 [24].
It is noted an apparent growing of grain size relative to grain size just after the PAW process.
Mohandas, Microstructure, hardness and residual stress distribution in Maraging steel gas tungsten arc weldments, Science and Technology of Welding & Joining, Volume 13, Number 4 (2008) 388-394

The least significant numbers of porosity were in rectangular ducts of 2.964 gr/ml.
The results showed that the cross-sectional shape of the duct influences porosity, hardness, and grain size.
The greater the percentage of porosity of metal, so lower the hardness value of the metal, and the larger the grain size.
The table shows that the most significant Brinell Hardness Number is a product manufactured using a rectangular duct with an average of 102.5 BHN.
The Si element (black) is in the form of tiny, elongated needles, while the Al element is in the form of large white grains.

Melt treatments, such as grain refinement (Ti & B) or modification (Sr or Na) could also influence the mechanical properties.
Other critical variables are the casting microstructure (SDAS and grain size) and defects (porosity and inclusions), all of which are dictated by the melting and casting processes.
Mould type, chemical composition, grain refinement, Si modification, and heat treatment conditions were the model variables.
Due to the complexity of the model, a number of variables that did not have much of an impact on the model were removed (such as %Cu or %Sn).
An iterative approach was applied to optimize the number of PEs and hidden layers.

Results show that corrosion potential shuffle, corrosion current density reduced nearly two number magnitudes value, polarization resistance increased, the cathode polarization effect enhanced obviously in polarization curves, and self-corrosion current reduced, impedance increased twenty times in alternating current impedance atlas than A3 steel substrate without coatings.
Fig. 1 was the surface coating SEM morphology of A3 steel made by pulse composite plating, it shown the coating uniform and stable structure in crystalline phase, crystalline grain was closely combined on the matrix.
The corrosion current density decreased almost two number magnitudes value, and deactivation area was very long.
The coating grains of Aluminum powders with nickel film by pulse composite plating was uniformity and densification, the coatings combined well with A3 steel matrix.
Corrosion potential shuffle, corrosion current density decreased nearly two number magnitudes value, the impedance of A3 steel with the coatings was 20 times more than ordinary carbon steel.

In the structure of network, input node is mostly decided by the problem, the key lies in the number of the implicit layer and implicit layer node.
Many scholars did study on the number of the implicit layer theoretically, considering if the node number can be chosen in a proper way, an implicit layer can approach a nonlinear function in any accuracy.
Correspondingly, the selection of the number of the implicit layer node is more difficult.
If the number was small, it is impossible for learning process convergence, and the node number is large the network function will be descend, and the node will be redundant [4].
The grinding burning and chatter can be measured with the electronic microscope, and grinding wheel dull degree can be obtained by the easy copy method, that is, the surface abrasive state of grinding wheel can be gotten by rolling and pressing the grinding wheel on the paper with very thin carbon powder, then acquire the grinding wheel surface's copy diagram with the microscope, and calculate the ratio of no carbon powder area (white in diagram, representative the bluntness sand grain to wear away surface) and carbon powder area (black in diagram, representative grinding grain wear surface), and the size of that ratio have a good rightness with bluntness grinding grain tip which can be used to certain the grind wheel dull degree.

EDS confirmed the presence of Mo in the crystalline grains and the presence of B in the amorphous grains. 211Mo Intensity (arb. unit) Fig. 3 XRD profile of the Mo–B foil. 2θ (degrees) 002Mo (b) [011]Mo (1) (a) 0.5μm (c) (2) Fig. 4 TEM image of (a) the Mo–B foil and SAD patterns from (b) grain (1) and (c) grain (2).
The average grain sizes of samples with SiC substrates prepared by CVD (Fig. 5(a)) were 3–5 µm.
When the Mo–B foil was used, the formed grains appeared larger than those formed from the Ti interlayers.
These figures denote the locations of the SAD pattern as numbers.
We performed detailed phase identification by analyzing the SAD patterns from 20–30 grains in each sample.

Optimum transplanting spacing effected to tiller, biomass and number of grain panicle-1 [5].
The data recorded on number of tillers, number of panicles, plant height (cm), panicle length (cm), canopy (cm), and circumference (cm).
Three seedlings hill-1 gave highly significance in number of tiller (avg. = 24.13 tillers hill-1) and number of panicle (avg. = 18.38 panicles hill-1) as showed in Table 2.
The highest number of panicle, grain yield and harvest index (%) were obtained in 3 seedlings hill-1.
Three levels treatments of seedlings hill-1 gave highly significantly in number of tillers (avg. = 24.13 tillers hill-1) and number of panicle (avg. = 18.38 panicles hill-1).

The change of grain and grain boundary toughness can dramatically change the fracture behavior of the composites [17].
Its grain boundaries and triple grain junctions are shown in Fig. 10.
Triple grain junctions in sample 4.
Zener pinning is very important in materials processing as it has a strong influence on recovery, recrystallization and grain growth.The small additions of TiO2 in the samples in the present investigation did not have any obvious effect on matrix grain size during sintering at a particular temperature (see Table 1) and only a limited number of larger matrix grain section areas were present.
Also TiO2 may promote a more homogeneous grain size distribution by solute pinning of grain boundaries [34].

The grind-hardening process integrates heat treatment processing into the production line, reduces the number of producing procedures, shortens machining period and lowers the cost.
Table 1 Chemical composition of SKD-11 (in weight) Element C Cr Si Mn Mo P< S< V≤ Content [%] 1.40-1.60 11.0-13.0 0.40 0.60 0.80-1.20 0.030 0.030 0.20-0.50 Table 2 Grinding parameters Specimen number Grinding speed [m/s] Feed rate [mm/s] Grinding depth [mm] Remarks 1 19.6 6 0.03 2 19.6 6 0.08 3 19.6 6 0.12 4 19.6 6 0.15 5 19.6 3 0.10 6 19.6 6 0.10 7 19.6 10 0.10 8 19.6 15 0.10 Down grinding, Without coolant In the experiment, the grinding force was measured by Kistler model 9272 four-component piezoelectric dynamometer, and the grinding temperature was measured by thermocouple.
Fig.4 shows the metallurgical structure of Specimen 1 and 2, which compared with the metallurgical structure of bulk material shown in Fig.3, indicates homogeneous dark grains filled in the material of the surface layer.
As shown in Fig.6(a), a white layer about 50~80µm thick with the fine and homogeneous grains and the small size circular carbides was formed by secondary quench occurring in the grinding surface.
1800 Grinding temperature (℃) Grinding depth (mm) 0.03 0.18 0.12 0.08 (a) Plot of grinding force (b) Plot of grinding temperature Fig.2 Plot of grinding force and grinding temperature Fig.3 Metallurgical structure of (a) Specimen 1 (b) Specimen 2 the bulk material (1000×) Fig.4 Metallurgical structure of the bulk material (1000×) 0 400 800 1200 500 550 600 650 700 750 800 850 900 950 Micro-hardness (HV) Depth (um) specimen1 specimen2 specimen3 specimen4 Fig.5 Distributions of the micro-hardness under the grinding surface Specimen 3 Specimen 4 (a) The hardened layer (b) The transition layer (c) The dark-etching layer Fig.6 Metallurgical structure of the surface (1000×) The existing research indicated that a low deformation degree would promote the nucleation of martensite transformation and be beneficial to the formation of small grains

Grain refinement can markedly increase the strength as well as improve the toughness of the metals [5-7], and it is also reported that some metals with nano-grained/ultrafine grained structures have positive effects on the biochemical response to surrounding media [8].
It was noticed that ultrafine grained steels with grain sizes below about 1μm offer the prospect of high strength and high toughness with traditional steel compositions.
The uncontrolled grain growth induced by the temperature used in conventional sintering must be avoided.
The increase in specific surface together with the decrease in particle/grain size accelerates the kinetics of grain growth.
Micropores were trapped inside the reduced grains.