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The present study was undertaken to explore the possibility of further grain refinement by increasing the number of passes and lowering the temperature of deformation in subsequent passes, and the associated texture development.
After 1 pass of ECAE, the grain size reduced to 6 µm.
The grain size distribution was found out to be unimodal.
The strength of texture fibers was analyzed through f(g) vs. number of ECAE passes (Fig. 7).
Editors, Ultra fine grain Materials II, Warrendale, PA: TMS, 2002, 643

The purpose of the study is to determine the influence of the type of plasticizers used for water activation on the speed of structure formation and the strength of fine-grained concrete.
However, the availability of such cements in a significant number of cases is significantly limited and requires solving the problem of organizing their search and transportation in sufficient quantities.
The problem lies in the clearly insufficient number of existing methods of calculation, construction and organizational and technological measures to ensure a high rate of concrete hardening.
Aim of Paper The purpose of the research is to determine the effect of ultra-low doses of plasticizers of various compositions on the strength of fine-grained concrete and the rate of formation of its structure.
Shishkin, Research into effect of complex nanomodifiers on the strength of fine-grained concrete.

The grain size increased dramatically in the center of fusion zone and the grain grew perpendicular to the fusion line at the boundary of the fusion zone that compared to the base metal.
The coarse grain zone of the base material was near the interface to the fusion zone.
Adjacent to the coarse grain zone was the fine grain zone.
Lower the heat input by means of increasing the welding speed conduced to the reduction of grain size in the fusion zone and coarse grain zone, which was beneficial to the improvement of the microstructure of the joint.
HAZ FZ BM Fig.5 Microhardness profile of the joint Table 4 Welding parameters used in the experiment Sample number 1# 2# Tensile strength(Mpa) 280 301 Summary A good appearance and defect-free joint of QCr0.8 bronze can be obtained by electron beam welding.

While both grain sizes and density of sintered samples were found increased from 1.4 μm to 2.46 μm and 90% to 98%, respectively.
The quantitative analyses were carried using the Rietveld method in Xpert Highscore Plus software to further clarified the number of phases formed accurately (as per Table 2).
The average grains size were observed 2.46 um.
Fig. 4: Average grain size of YAG with different sintering hour Density measurement: The relative density and grain growth of sintered YAG at various sintering temperatures and is shown in Fig. 5.
It is generally known that both the average grain size and density proportionally increased with longer holding times.

Microstructural parameters covered included the morphologies of martensite, the sizes of the prior austenite grains, grain sizes and grain boundary misorientations, and the number density and size of precipitates.
Results and Discussion Number density, size and chemical compositions of NMIs.
The total number of NMIs decreased by 7% as a result of ESR.
The number of NMIs per mm2 in all size ranges decreased as a result of ESR except the number of NMIs per mm2 in the size range 6-10 µm which remains unchanged.
Using Image J software, the numbers and sizes of all precipitates were calculated.

It can be seen that the number of cleavage planes of Alloy Ⅰ is higher than Alloy Ⅱ.
However, the number of dimples shows the opposite trend.
The curves of crack length versus the number of cycles (a-N curves) are presented in Fig. 3(b).
It can be seen from Fig. 5(a, c) that fine recrystallized grains ( the green part in the picture ) are scattered in the alloy and the number is small.
In general, the FCP rate is smaller for alloys with coarse grain size than for those with fine grain size.

The fatigue behavior of metals is strongly governed by the grain size variation.
In many microcrystalline (mc) and ultra-fine grain (ufc) metals and alloys, strengthening with grain refinement has traditionally been rationalized on the basis of the so-called Hall-Petch mechanism [2, 8].
Here the increased resistance to plastic flow is explained as depending on the pile-up of dislocations at grain boundaries and to the mechanism associated with the much more difficulty of the slip transfer between adjacent grains.
Even if a grain refinement leads to an increase in the number of cycles to failure at the same stress levels investigated, the results for very close microstructures results a strong function of the ductility.
The dislocation generation and locks formation is larger as decreasing grain size because of the grain boundary density, in this way the more the structure is fine the more such phenomenon is pronounced and the hardening increases as decreasing the grain size.

Three different casting process parameters were specifically designed The number (Table 1.) is poured into test bar with residual size, and the main chemical composition measured by direct reading spectrometer is shown in Table 2.
Serial number Alloy Shell temperature (℃) Pouring temperature (℃) 1 K4169 950 1410 2 950 1460 3 1050 1500 Table 2.
It can be seen from the figure that the alloy structure has a typical dendrite morphology, and there are a large number of island-like Laves phases between the dendrites, which are continuously distributed, as shown in Fig. 2(c).
It can be seen from Fig. 3(b) that after heat treatment of group B, the Laves phase and the needle like δ phase around the dendrite and at the grain boundary are basically eliminated, and only a small amount of Laves phase and MC type carbide are left.
After heat treatment in Group F, a large number of Laves hard and brittle phases formed by segregation of Nb elements remained between the dendrites.

The methods of local form-shaping of the parts under SP [5] conditions allow to solve the problem of fabrication of the complicated axisymmetric parts provided a minimum metal loss, without application of powerful press equipment and massive forging tools and with minimum number of operations.
In this case the main mechanism of deformation is grain boundary sliding.
Therefore, in the rim of the disk it is important to have coarse-grained structure that give the material heat-resistance, and in the hub it is important to have fine-grained structure that provides higher strength.
It is characterized by a combination elongated in the radial direction coarse grains separated by thin layers of fine grains; this structure is typical for thermal deformation.
The experiments on generating disc regulated structure and its properties are described sufficiently detailed in a number of papers [1, 11].

The neighbouring cells of type Liq from its nearest environment (N, S, W and E) are captured by the growing grain, thus creating type Int-2 with all the attributes of a grain of this type (i.e. number, orientation angle of crystal lattice, and phase type in the case of multiphase growth).
The neighbouring cells of type Liq present in the nearest vicinity are absorbed by the growing grain and acquire type Int-2 with all the attributes of a grain of this type.
The neighbouring cells of type Int-3, belonging to this grain, change their type into Int-2.
The attributes of none of the 8 closest cells will change, if the cells have already been captured by other grains.
In these equations the subscripts n and n+1 denote the iteration number, and the superscripts denote the indices of the neighbouring cells (see: Fig. 1).