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A certain ceramics density decline sintered at 1750°С is specified by the concentration grade growing of dioxide zirconium monoclinic phase due to the recrystallization growth of grains.
Ceramics and Titanium cermet density at different sintering temperatures Number Sample Density*, [gr/cm3] 1550 °С 1600 °С 1650 °С 1700 °С 1750 °С 1 CZC 4.03 4.80 4.81 4.94 4.84 2 OC-1,25 4.72 4.72 4.69 4.55 samples melted 3 OC-2,5 4.67 4.64 4.37 3.85 *For studied compositions the ceramics theoretical density equals 5.03 gr/cm3.
Therefore, the recrystallization growth of grains must be significantly decelerated in the issue of sintering activation energy reduction and a low motion speed of phase boundaries.

The grain size of HAZ was smaller than base metal, because of the welding heat input effect.
Ferrite and pearlite appeared in HAZ and base metal, but the HAZ grain size was smaller.
In the carbon steel SS400, weld metal had higher hardness number ​​than the base metal and HAZ due to bainite microstructure. 3.

Values for the dielectric properties of a number of products, including grain and seed, fruits and vegetables, and poultry products, depend on frequency, moisture content, and temperature. [5] [6].
Free-space measurement of dielectric properties of cereal grain and oilseed at microwave frequencies.

The principal component can compress a certain number of variables into several separate components, in order to reduce mutual interference among the variables.
According to the principal components analysis and the data collected in Hefei city, the data from 1998 to2009 were chosen as the bases, and nine affecting factors were selected, including:X1- the total population (10000 persons),X2- agricultural population(10000 persons), X3- gross domestic product (100 million yuan), X4- the second the tertiary industry product (100 million yuan), X5- total grain output(kg), X6-total agricultural product(100 million yuan), X7- grain yield per ha (kg/ha), X8- increase investment in fixed assets (100 million yuan), X9- per capita road area(m2),Y- area of cultivated land (ha).

Chemical composition of 3D printed MCM MATERIAL Chemical composition [%] Fe Ni Cr O Nb C Al Tl Ti MCM 37,7 27,7 12,4 7,4 5,3 2,8 2,4 2,2 2,5 SEM analysis of the 3D printed MCM material provides detailed images of the microstructure (grain size and shape), highlights the quality of the bond at the interface between the metal matrix and the reinforcing particles, including any defects or voids, and is shown in figure 4.
In order to determine the optimal welding parameters and their influence on the quality of the obtained welds, a number of 4 samples from the 3D printed MCM were tested, following the variation of the following parameters: - welding time; - welding energy; - frequency of ultrasound; - ultrasound amplitude; -pressing force or pressure.
The 3D printing manufacturing process generates a heterogeneous microstructure with variations in grain size and distribution leading to non-uniform welding behavior.

While welding the alloy of Al-Mg-Li system (alloy 1424), after quenching and quenching with ageing we can see the decrease in the number of dark and light gray aggregates, however, it is still enough to define the fir-tree structure grains clearly.
Effect of two-step aging on recrystallised grain size of Al–Mg–Li alloy, Materials Science and Technology. 27 (2011) 125-131

Such influences promote the formation of a fine-grained structure and increase the mechanical and operational properties of castings without the addition of special modifying additives.
The change in external conditions, for example, temperature, leads to a change in the structure of the short-range order (interatomic distances, coordination numbers, the geometry of the disposed atoms, and the sizes of the ordered cluster complexes).
The resulting excess of nuclei of crystallization determines the formation of an extremely non-dendritic structure with a grain size approximately equal to the size of the dendritic parameter.

A number of fabric layers circular in shape, were stacked together.
Etching with 40% HF solution for 22 h delineated grain boundaries.
The deep cavities indicate the spalling of smaller grains.

Under the action of the applied load the high manganese austenitic TWIP steel will produce a large number of mechanical twins, and these twins boundaries are acting as strong barriers to subsequent dislocation motion, which significantly improve the hardening rate of materials, delay the necking, and result in the high ductility of high manganese austenitic TWIP steel[3].
It can be seen that the microstructure is austenite, the grains are fine and annealing twins existed, the average grain size is about 60μm.

However, only a limited number of investigations concern the direct heating of steels for the phase transformation, therefore, receive a superficial layer of the appropriate thickness, free of cracks and with high hardness.
The high energy density plasma arc could create a high cooling speed of the hardened layer at the surface just like laser, thus leading to the formation of superfine grains [12].
Martensite formed in the surface hardened layer has the properties of high hardness, fine grain size inherited from the substrate and severe dislocation.