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And we found that a lot of dispersion particle V(CN) precipitated in the ferritic matrix and grain boundary place, which have a good precipitation strengthening and refining grain effect.
V micro-alloy sample of relatively small grain and pearlite content was less than that on the hot-rolled samples .This is due to controlled rolling and cooling, by controlling the rolling temperature and cooling speed to improve the nucleation rate of austenite, to inhibit the growth of austenite grain by grain refinement element V.
Rm / MPa Rel /MPa A gt / % A /% Rm/Rel 1 624 494 13.1 22.4 1.26 2 737 567 13.5 24.4 1.29 3.3Micro-alloying elements distribution and precipitated phase In the design of steel on the No.2 of the trace elements V, by scanning and analysis of small regions, Micro-alloying elements V distribution in the grain boundaries and within the number is somewhat different.
Fig 2 Test steels grain and grain boundary distribution of alloy elements of NO.2 (a) inside the grain distribution of element V (b)the interior of grain distribution element spectrum ( c) near the grain boundary distribution of element V (d) near the grain boundary distribution element spectrum Steel micro-alloy elements in the general strengthening effect from the steel by solid solution strengthening and precipitation strengthening.
[7] Weng Yu-qing.The ultra-fine grained steel - steel microstructure refinement theory and controlled technology [M].

This was because with the increasing of aggregate grain, the grain which have not plasticity would increase relevantly, the content of flux in high temperature decreased, and the filler of pore space was relevant less, so the porosity increased and bending strength decreased.
Among them, the residual quartz grain and glass phase of 2B were more, 10B was evident decreasing and the 14B was the least.
This shows, with the increasing of ceramic aggregate, the main composition was mullite grain, the residual quartz grain and glass phase reducd, the samples porosity, high temperature flux and bending strength also reducd.
When ceramic aggregate grain reached 60%(or 14B), the fusing filtration materials reduced, the grain which not melted increased, so porosity was highest, strength reduced apparently.
of small pores were well-distributed; when D is between 120µm and 90µm(120~160 mesh sieve), the number of small pores was much, the shape of pores was more regular and smooth, but the connection of pores was worse, this was because smaller grain size and parts of grains were fusing.

Thus, the silver grain deposits by the hydrogen atom which existed on the surface of the specimen.
These phases are easily distinguished at the SEM observation because of the difference of the atomic number of Mg and Ni, that is, the Mg phase and the Mg2Ni phase show dark and bright contrast, respectively.
These white precipitates are confirmed to be silver grains, as mentioned in Fig.2.
The silver grains are not observed on the Mg rich phase but the Ni rich phase.
The silver grains are also observed on the Ni rich phase, i.e. the Mg2Ni phase.

The grain structure of the alloy is characterized by randomly oriented ultrafine bcc α-Fe(Si) grains (10-20 nm), uniformly dispersed in a residual Fe-Nb-B amorphous matrix.
Using appropriate heat treatment it is possible to control the material structure and magnetic properties by altering number and composition of Fe(Si) grains [2].
The agglomerates formation was not observed with increasing of the annealing temperature that was the reason of grains number increase per the scan area (Fig. 1(c)).
Average diameter of the grains was of about 55 nm for films annealed at 540 ⁰C.
Recrystallization at 540 ⁰C and formation of a large number of grains with the uniform dispribution of magnetization anisotropy axes lead to enhancment of the shape magnetic anisotropy instead out-of-plane one (Fig. 2(d), curve (3)).

While the grain orientation in bulk samples was random the grains in the thick films were aligned along the substrate plane.
BLSF have the general formula (Bi2O2) 2+ (Am-1BmO3m+1) 2, m is the number of BO6 octahedral layers in the perovskite slab.
The observed grain growth rate in thick films was much higher than in bulk ceramics.
The grain orientation was more pronounced in the films sintered at higher temperatures.
Thicker films had smaller degree of grain orientation than thinner films.

It used variable speed of rotor on slag liquid centrifugal graining.
The slag after being thrown out under the effect of ultra-high cold wind cool rapidly achieved the process of grain.
Set-up of Air Inlets Number.
After the division, the grid number was about 1.7 million.
As the numbers of inlets are less than eight, the internal flow field is more stable and the eddy current is small with the increase of the numbers of inlets.

As a consequence, the retained austenite grains in TRIP steels possess different carbon content or grain size, leading to a range of stability as illustrated in the literature [1].
It was experimentally determined that phosphorous refines the grain size of ferrite and bainite but no statistical data on the grain size of retained austenite is available.
Quantitative analysis of the images gives the total number, the area and the aspect ratio of each particle.
The discrepancy might be related to the shape and orientation of the austenite grains.
Therefore, neutron depolarization measurement leads to a much smaller grain size in P0.14 steel than that from the image analysis as the neutron beam transmitted through the thin part of the austenite grain.

Moreover, it has been proved that slight changes in the hysteresis loop parameters, as a function of the number of stress cycles, have a significant influence on the obtained material data used when calculating the life.
The size of ferrite grain determined using pictorial standard models [8] amounted to 5, which corresponds to the mean diameter of grain amounting to 62.5 μm.
On the boundaries of ferrite grain in the examined steel, both single and numerous carbides of diverse size were observed, forming the so-called „continuous grid” of precipitates in some areas.
The precipitation of the M2C and MC type were revealed inside the quasi-polygonal ferrite grains, while the M7C3 precipitates were seen mostly on grain boundaries and in bainite.
Fig. 5 shows the changes of these loop parameters (Deap, Dsa), as a fuction of the number of cycles in one block of loading recorded in various periods of fatigue life.

Two coarse-grained granitic rocks - charnockite and biotite granite – were studied with the aim of estimating their unconfined compressive strength from simpler non-destructive test values.
A set of properties – colour, grain size and shape, strength and durability – characterizes a rock.
Among the commonly used parameters are ultrasonic pulse velocity [2] and Schmidt hammer rebound number [3].
Near-surface moisture contents of coarse grained rocks like the charnockite can lower the rebound readings appreciably.
The number of samples used in rock study is usually hardly representative of the rock mass in question.

Although during billets drawing in this tool a fine-grained structure and the necessary level of mechanical properties of forgings for a smaller number of passes is ensured, there is a larger change in the billet initial dimensions compared to the step dies.
Billets with the same sizes were deformed in the old designed step-wedge dies and step dies with the same number of passes as during deformation in the newly designed step-wedge dies.
To determine metal grain size deformed by the proposed and current technologies GOST 5639-82 "Methods for detection and determination of grain size" was used.
Optical microscope OLIMPUS BX53M was used to determine grain size.
Ghosh, Production of ultrafine-grain microstructure in Mg alloy by alternate biaxial reverse corrugation, Acta Materialia, 54 (2006) 5147–5158