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While the fixed abrasive lapping technology had a number of advantages such as higher efficiency, lower cost, and process controllable and green process.
The abrasives used were micro powder diamond grit with grain size about 40μm, and the flatness of fixed abrasive lapping disk was not greater than 120µm.
It could be due to the increase of wafer velocity improving the abrasive grains participated in the grinding action per unit time.
With the increase of workpiece velocity, the abrasive grains participated in the grinding action per unit time increased and the removal rate would be bigger.
It could be seen that removal rate of the workpiece ground by the symmetrical disk was bigger than which ground by spiral disk and decreased with increasing of grinding time, This was because, with the increase of grinding time, the diamond abrasive grains were gradually wear, the blades participated in the grinding were becoming less.

Unlike alloys with equiaxed grains, the columnar grain structure of these castings eliminates grain boundaries perpendicular to the primary tensile stress axis.
This microstructural feature significantly enhances creep resistance by limiting the initiation and propagation of cavitation and cracks along grain boundaries.
The precipitates composed of high atomic number elements, appearing as bright-contrasted precipitates, were identified as MC carbides.

Experimental Procedure In order to break coarse grains and eliminate the defects formed in the casting process, the forging process of β20C titanium alloy has to be implemented.
As Fig. 5 illustrates, there is dynamic recrystallization happened at grain boundaries in the process of heat treatment.
In addition, it is clear that the number of “feathery structures” reduces if compared with Fig. 3.
Subramanian, Modeling of critical grain size for shifting plasticity enhancement to decrease by refining grain size, Material Science & Engineering A 607, 2014

Heat treatment of thixoformed products Work done with wrought 7000 series aluminum alloys at Sheffield [15,24] showed that thixoformable feedstock should adopt a three step induction heating regime, in order to avoid excessive grain growth, with short holding intervals at 475 °C (1 min), 575°C (1min) and a short 20 s hold at the final step at 620 °C, generating grain sizes of feedstock less than 100 µm, which is suitable for thixoforming [15].
Finally, SIMA or RAP routes can be used to generate high quality of feedstock but are appropriate for batch manufacturing rather than the production of large numbers of parts.
Thixoforming has been successfully producing complex near net-shape parts for a number of industries in a number of aluminum and magnesium alloys, however, to date it has only found commercial success in few cases and it is clear that this is a manufacturing process with commercialization potential if introduced into the correct markets [29,35,38].
Flemings, “Grain refinement of an aluminum alloy by introducing gas bubbles duringsolidification,”Scripta Materialia, vol.55, no.2, pp.115– 118, 2006 [8] J.
Zhuang, “Roles of Alloy Composition and Grain Refinement on Hot Tearing Susceptibility of 7xxx Aluminum Alloys”, Metallurgical and Materials Transactions A, Volume 47A, August 2016, pp 4080-4091 [15] Chayong, S.; Atkinson, H.V. and Kapranos, P.

This combination of properties and the particular structures of HEAs are attractive for a number of potential engineering applications.
Non-metallic elements may be for example carbon, boron, silicon, phosphorus, sulfur, hydrogen, oxygen, nitrogen and so on.[2,3] It was found that alloys with a higher number of principal elements are more likely to form simple disordered solid solutions (e.g., simple fcc and bcc structures) during solidification, rather than intermetallic compounds.
Can be observed grain boundaries.
As Al content increases, the morphology of the microstructure varies and the grains coarsen.

The increase in soaking temperature increases the size of the nanocluster, which decrease the volume fraction and number densities.
The NFAs contain an ultrahigh density of Y-Ti-O enriched nanofeatures along with fine grains and high dislocation densities.
The nanoclusters formed, are deposited in the grain boundaries thereby preventing the dislocation motion and hence the enhancement of creep properties.
Increasing consolidation temperature results in larger NC sizes and smaller number densities and volume fractions

There have been many studies on thin layer drying of agricultural grains and leaves [6],[7],[8],[9],[10],[11],[12].
The initial and final moisture contents of the grain were measured using the oven-drying method in which 10 g of the grains of sesame were dried at 130 °C for 6 h as recommended by Young et al.[20] for oil seeds with high oil contents.
The change of the grain moisture content, with time, was calculated from the mass change data.
(6) where Mm = measured moisture content (% w.b.), Mp = predicted moisture content (% w.b.) and N = number of observations.
Cenkowski, Grain Drying: Theory and Practice, John Wiley & Sons Inc., New York, NY, 1998

The increasingly large number of vehicles led to global limitations concerning carbon dioxide emissions.
Inside the grains, round shape particles were observed and identified as dispersoid particles.
Grains are clearly visible in agreement with an intergranular fracture but a thorough analysis revealed that the surfaces of the grains are covered by dimples (Fig.4 (b)) related to the η-MgZn2 intergranular precipitates [14], [15].This fracture mode is well known for 7xxx aluminium alloys.
These intergranular cracks could be related to hydrogen enrichment at grain boundaries.
The brittle intergranular fracture observed was attributed to the trapping of hydrogen at the grain boundaries.

The number of electrons is reduced at the conduction band.
Under the UV irradiation, the barrier height of the grain boundaries is lower, hence affects the mobility in ZnO grains [27].
ZnO films with higher substrate temperature have bigger grain size, as reported in our previous work [15], which means that there exists much less grain boundaries in the films with larger grain size.
With the increase of grain size, the dark current decreases, and the photocurrent increases [32].
The photocurrent response is enhanced with improved structural properties of the ZnO active layer with bigger grain.

In the method that the oxygen-free copper strips are produced through undercurrent horizontal continuous casting-cold rolling process, there are some coarse grains, microscopic cracks, shrinkage, shrinkage and segregation defects in the oxygen-free copper strip billet, which debase the densities of the strip billet, and are the main reasons for rejected castings during machining operation.
If continuous casting process factors and their combination were not reasonable, coarse grains, microscopic cracks, shrinkage, shrinkage and segregation defects would exist in casting blank[3] [4].
Symbol n represents the number of neurons in the superior networks.
The study phase adopted Levenberg-Marguardt algorithm, the basic iterative formula was Eq.5: (5) In which g represents the grads of error function for the weight vector, J represents the Jacobi matrix of error function for the weight vector differential, I represents unit matrix, u represents an adjustable nonnegative number.
At the same time, reduce the number and cost of the actual experiment while enhance the economic benefits.