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The mechanical properties are decided by microstructures formed during CF&C processes, and structures variables controlling properties are: austenite grain size (AGS), ferrite volume fraction (f %), interlamellar spacing of pearlite (S0), and volume fraction and size of precipitates.
During this short process, a large number of unmelted cementite lamellar (fig.4a) will form network sub-structures which prevented the movement of austenite grain boundary [4].
With technologic parameters being optimized the surface austenite grain size number to ASTM 10 of FAS2340, but it is ASTM 8 in 42CrMoH.
The contents of Fe3C in second phase particles are exceeded 90% and the Fe3C particles (diameter: 10~18nm) are more than 70%, the tiny particles can effectively prevent the movement of grain boundary of austenite (fig.4b) and play an important role in the refinement of FAS2340 steel surface microstructure.
The structure controlling variables are ferrite/pearlite volume fraction (f％)and Grain size (Df) of ferrite [8-11].

Thus, a number of articles have used either sulfide addition or H2S saturation to study HE in DSS [18,19,20,21, 22].
The fracture was also found to initiate in the ferrite grains.
The fracture surface revealed cracking predominantly of the ferrite grains.
A selective attack of the ferrite grains and grain boundaries could be identified.
When the grain boundary precipitates were predominantly active in the fracture, the fracture was naturally intergranular, cleaving adjacent ferrite and austenite grains.

The semicircle region of the impedance spectra may be due to the bulk (grain) conduction of the material and the low frequency spike to the grain boundary effect observed and reported by various authors for different systems.
The intercept of the arcs (attributed to the grain (bulk) and grain boundary phenomena) with the real axis gives an estimate of bulk and grain boundary resistance.
The semicircle region of the impedance spectra may be due to the bulk (grain) conduction of the material and the low frequency spike to the grain boundary effect.
The intercept of the arcs (attributed to the grain (bulk) and grain boundary phenomena) with the real axis gives an estimate of bulk and grain boundary resistance.
It can be ascertained that due to the increment in number of charge carriers for conduction which decreased the resistivity of the samples.

During annealing, small grains recrystallize to form larger grains [1].
The average grain size increases with Ca concentration.
The grains in all samples appear to stick to each other and agglomerate.
A large number of fine particles along with relatively large irregular particles can be identified in micrograph Fig.1 (b).
Furthermore, needle-like grains can also be easily identified in sample Fig. 1(d).

The addition is Cr3C2 and VC with a grain size being 2.35um and the purity being more than 99%.
This can be attributed to the grain growth during the fabrication process.
Meanwhile the VC and Cr3C2 can prevent the grain from growing greatly.
There exist toughness sockets and also a small number of gas pores.
Conclusions With the increasing of the temperature, pressure and heat retaining period, the grain size of the material grows, the one playing the most important part is the temperature, and reasonable temperature controlling is the key to control the grain size growth.

Nanocrystalline materials have different properties compared to materials with microcrystalline grains.
Dividing the materials as finely as possible ensures a better reactivity due to the free valences of the ions on the surface of the granules and due to the fact that the number of contact points and the contact surface are much larger than in coarse-grained materials.
The high values of the magnetic parameters for nanometric materials can be explained by the fact that the grain volume did not increase as much as the grain volume of micron-sized materials during sintering.

The main characteristics of sand as a construction fine aggregate are: sand grain size module, grain composition, grain surface type, mineralogical composition, intergranular voids, presence of various impurities [2].
Sand of medium and large groups is usually used in construction as an aggregate for heavy, simple, fine-grained, coarse-grained and silicate concrete, concrete mixtures, in the manufacture of reinforced concrete structures, used in the production of asphalt and road surfaces (the proportion of sand in road asphalt reaches 90 %).
A type of sand Water yield coefficient μ Coarse-grained, gravelly sands 0.25–0.35 Medium-grained sands 0.2–0.25 Fine-grained sands 0.15–0.20 Dusty sands 0.10–0.15 According to [14], there are industrial methods of dewatering sand, which, according to the nature of the physical process of removing moisture from the material, are divided into mechanical methods and thermal drying.
However, this solution has a number of serious drawbacks, namely the decrease in the quality of mined sand due to the uncontrolled fluctuation of its moisture level, which often leads to the negative consequences of disrupting the technological process of manufacturing concrete, construction mortars and mixtures, and ultimately to a decrease in the quality of products.
As a result of the study, it was established that the moisture content of coarse-grained sands can be obtained within 2.5–4 % and 7 % for fine sands.

To compare the plasticity d* and d*H (determined in indentation for a large number of materials), it seems reasonable to determine d* at et = 7.6 % as well.
However, the elongation at fracture d for a number of metallic alloys is less than 7.6% in mechanical tensile tests.
Such dependence is broken for the nanosize grains, where the mechanism of plastic deformation changes substantially.
We produced dependency d*(et) for a number of steels and of aluminum alloys, and established correlation between d* and plastic strain at fracture d. 3.
Froes, Grain size effects in nanocrystalline materials, J.

In comparison to the conventional forging, forming aided by shear stress is able to provide a number of benefits such as significant increase of local strains, lower press loads and the opportunity to control the strain distribution in the workpiece volume.
A significant grain refinement and controlled improvement of functional properties of a product can be obtained this way [9-11].
So far, a number of relevant FE simulations has been performed in Transvalor’s Forge2009 software in order to evaluate the effect of forming conditions on the press load and the effective strain distribution in a workpiece.
Čížek, Grain refining of Cu and Ni-Ti shape memory alloys by ECAP process, J. of Achievements in Materials and Manufacturing Engineering 20 (1-2) (2007) 247-250
Tkocz, Deformation-induced grain refinement in AlMg5 alloy, Solid State Phenom., 191 (2012) 37-44

Increasing Al content results in the size of γ+γ´ eutectic and the number of γ´.
Numerous beneficial effects are demonstrated that grain boundary crack destroyed turbine blades[7].
The insufficient resistance against grain boundary in some superalloys prevented the application of directional solidification processing in certain alloys.
Variation of crack microstructure on element compositions It can be seen from Fig.4 that the size, number and patten of (γ+γ´) eutectic change with increase of Ti content. γ´ phase without any as Ti content in IC10 was the least.A further increase in Ti content to 0.8% resulted in larger size and number than IC10.
Tube castings display severe cracks with the increasing of Ti content because of either eutectic with larger size and number or total freezing range.