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This effect is obviously associated with the process of precipitation of the dispersed a-phase during the decomposition of the metastable a”, b-phases formed in the HAZ after welding, the number of which gradually increases with distance from the parent metal zone getting a maximum of 100 % near the weld [6].
Then hardening somewhat decreases due to the coarsening of the metastable structural components owing to the growth of the β-grain.
As shown by structural studies, the reason of the heterogeneity is the difference in distribution and location of the decomposition products of metastable phases, i.e. the decomposition of metastable phases during aging at 500 °C for 8 hours occurs mainly in the internal volume of the β-grains and sufficiently homogeneous, while the decomposition during aging at 550 °C for 8 hours is realized both in the internal volume and from the boundaries of β-grains and the β-solid solution volumes free from precipitates are preserved.

This is consistent with results of molecular dynamics simulations on the average coordination number calculations.
Lighter isotopes and heavier isotopes contain the same number of atoms.
Number of particles ND which are moving cooperatively in a basic diffusion event for Cu isotopes in Cu-Ag liquid alloys.
Number of particles ND which are moving cooperatively in a basic diffusion event for Ag isotopes in Cu-Ag liquid alloys.
Eich, A systematic study of grain boundary segregation and grain boundary formation energy using a new copperenickel embedded-atom potential, Acta Materialia, 176 (2019) 220-231

There are number of different techniques that facilitate the deposition of stable thin films of oxide materials on suitable substrates.
Not only there is a decrease in the number of atoms that deposit, but there is little compaction or modification of the resulting film structure [20].
Ramakrishna Reddy et al. [49] had a strong {002} preferred orientation with a grain size of 98 nm and exhibited the wurtzite structure.
The grain size along the c-axis is found between 15.4 nm and 27.3 nm.
The film deposited at 140 W has the narrowest FWHM and the largest crystal grain.

A large number of studies have shown that refining grains is an effective means to improve the strength and toughness of steel materials, and adding rare earth elements into molten steel is an effective method for refining grains.
The numbers of inclusions with size of 5~10μm and size more than 10μm were equivalent, especially in the thickness direction.
The number of rare earth inclusions in sample No.2 was small.
The rare earth elements La and Ce had a large number of inclusions with sizes of 1~5μm and 5~10μm, which were evenly distributed in the thickness direction, while the number of inclusions larger than 10μm was less.
For the addition of rare earth element after the RH furnace process, No.3 sample inclusions had a large number of rare earth element inclusions, which number was tens of times that of No.2 sample inclusions adding rare earth elements after the LF furnace process.

Results show a number of processes, including: i) change in subgrain boundary misorientation angle and ii) subgrain subdivision into areas of similar lattice orientation with new subgrain boundary formation.
In-situ heating experiments present a powerful technique and a large number of 2D studies have been conducted using in-situ heating stages inside the scanning electron microscope (SEM).
Results A number of observations were made, primarily qualitative, but some early quantitative results were also attained.
Juul Jensen, in: Recrystallization and Grain Growth edited by G.
Gottstein and Molodov, Proceedings of the first Joint International Conference of Recrystallization and Grain Growth, Aachen, (2001), p. 981 [19] C.

Test results show that the amorphous alloy coating have good corrosion resistance due to their homogenous microstructure and absence of crystalline defects such as dislocations, grain boundaries and precipitates[8].
When the amorphous coating was heated at 700°C for 2h(Fig.3b), a number of corrosion pitting were appeared on the surface of nano-crystalline coating, implying a low ability to withstand localized corrosion.
The results reveal that the corrosion resistance of annealed coating holding 2h in salt spray test was better than that of the coating holding 8h because of the smaller area of grain boundary and triple junction content in the nano-crystalline specimens, which provide sites for chemical reactivity. with the crystalline volume fraction of 99%, plenty of grain boundaries in annealed coating surface provide more defect sites, which will increase the chemical reactivity and accelerate the corrosion rate[[12] L.

Introduction The Lasioderma serricorne （Fabricius） (Coleoptera: Anobiidae) ranks as one of the most serious insects of stored tobacco, tobacco products, cereal grains worldwide (Kaelina et al., 1999).
The Petri dishe was covered and kept in incubators at 27±2 ºC and 75±5% r.h., and the number of dead insects was recorded after 24 h, 48 h, 72 h and 96 h.
Wu: Bioactivity of essential oil from Ailanthus altissima bark against 4 major stored-grain insects.
DC. and Elsholtzia stauntonii Benth extracts on three major stored-grain insects.

Usually the incubating agent is added to alloy melt, which can increase a large number of homogeneous nucleation in the metal melting and then refine the grain size of alloy [4].
Under SC (suction casting by water cooling copper mould) with much high cooling rate (3.5´104 K/min), the primary phase changed to d-AuSn phase (confirmed by EDS analysis) with very small grain in solidification structure (Fig.1d).
The grain size of eutectic lamellar colonies was refined from 16μm to 4μm by increasing the overheating temperature from 300°C to 420°C.

During the relatively slow cooling of cemented samples, the eutectoid decomposition of austenite does not lead to the formation of pearlitic colonies, but to the continued separate growth of cementite on the already existing cementite grains with the formation of a ferritic rim around these inclusions.
Acknowledgment This work was financially supported by the Ministry of Education and Science of the Russian Federation for the project № 11.2054.2017/ Project task within the framework of the state task for 2017-2019 (project number 11.2054.2017/4.6).
Kozhukhov, Formation of non-uniform grain structure of steel in the process of heat treatment and method of evaluation of microstructure with significantly non-uniform grain, Journal of Chemical Technology and Metallurgy, 52(5) (2017) 996-1001

Diamond tools can be used in ultra-precision machining of a number of hard materials to obtain mirror surface finish [3,4].
The surface roughness is mainly relevant to grain size and the second nucleation of diamond films.
The smaller the diamond crystal grain size is, the lower the surface roughness will obtained.
The sp 2-bonded amorphous carbon, increasingly present at high CH4 concentration, was shown to nucleate at the boundaries of the diamond grains.