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The deformation behavior studies entailed characterization of tensile behaviour in the temperature range 77K - 873K for the as received and the fine grained Nb modified variant of AISI 403.
The presence of Nb could alter the manifestations of DSA by reducing the grain size and forming NbC precipitates, which could reduce the susceptibility of the material for serrated flow by localizing the solute dislocation interactions near grain boundaries (Kutumba Rao et. al. [11]) as well increasing the mobile dislocation density content.
The feature-less areas containing few ductile dimples are signatures of the occurrence of the crack jumps, because as pointed out by Mohan and Marschall [15], they result in rapid separation of the crack faces leaving less time for large number of voids to nucleate during the ductile crack growth.
Refining grain size shifts the strain rate for the DSA to higher rates. 2.
RamaRao, The grain size dependence of flow and fracture in a Cr-Mn-N austenitic steel from 300 to 1300 K, Metall.

The Orthogonal Arrangement (OAs) Ln designates them, where n represents the number of test and the most common head offices are L4, L8, L9, L12, L16, L32 and others.
The choice of OAs is made using the method of the freedom degrees number [5].
The sintering can be defined in three stages: initial, intermediate and final, in the initial stage it happens the formation of the “neck” among the grains, not happening shrinkage, in the second apprenticeship, the intermediate stage, happens the contraction until the elimination of the open pores and in the final stage it happens the grains coalescence [7].
Fig. 4 - Grain Size in relation experiments of Niobium sintering.
In these conditions the samples presented approximately 65 mm of grain size and Vickers microhardness of the 95 HV, evidencing that how much larger the value of the microhardness, smaller the grain size.

Results Trial melt CB2 A relatively small number of isolated pores were observed on metallographic samples.
Size of prior austenitic grain was 238 μm.
Grains are formed of blocks of laths subdivided into subgrains.
Prior austenitic grain sizes were 225 μm and 229 μm in the position A and B, respectively.
Prior austenitic grain size did not change during creep test.

The main features of the investigated pollen grains are summarized in Table 2.
no ornamentation Note: The table number is consistent with Table As shown in Table 2, pollen grains of Morus were found to be conservative.
There were small circular pollen grains with 1–3 apertures.
They were Erdtman N3P3C4 pollen grains.
Cluster Analysis on the Pollen Morphology of Chinese Morus To obtain as much information as possible regarding the classification and phylogenetic relationships of Morus pollen morphology, 25 operational taxonomic units were established using DPS software, and cluster analysis of 7 characters (polar axis length, equator axis length, aperture diameter, size of the particles on the surface of the pollen grain, P/E value, features of prismatic layer ornamentation, and number of particles on the surface of the pollen grain/μm2 ) were performed.

Some difference of the dimension grain is visible.
Macrostructure of titanium Ti-6Al-4V alloy (a) before HTM, (b) after HTM The investigated Ti-6Al-4V alloy the in initial state, i.e. after full annealing within the β single-phase area temperature was characterized by homogeneous two-phase microstructure with average grain diameter of approx. 500 μm.
The alloy microstructure is represented by alternately arranged lamellar precipitations of α and β phases with different orientations in particular grains (Fig. 3).
At the same time, however, this was accompanied by a much greater number of microcracks.
The current state of knowledge and technological level allow for efficient forming of grain size of two-phase titanium alloys only during hot or cold working processes in conjunction with recrystallization annealing.

Meanwhile, some abnormal grain growth behavior also can be observed from Figs.
(b, c), which should be due to a large number of liquid phases appear in local areas under high LBSCA doping amounts condition.
On the other hand, the average grain size of pure CSLST ceramics is about 2 µm as detected by Fig. 3(d).
However, the addition of LBSCA glass apprantly reduces the average grain size to lower than 1 µm as seen from Figs.
This phenomenon should also be owing to the appreance of liquid phase during sintering, which makes the grains impinge upon each other and thereby inhibits the grain growth at the early stage of sintering [9].

During solid state sintering, diffusion is a mechanism of mass transport, where two spherical particles transform material from flat surface to neck and volume diffusion from the neck to the neck through grain boundaries exist depending on the sintering conditions.
A thorough analysis on MWCNT clustering over particle boundary, particle orientation and grain sizes was carried out using the electron backscatter diffraction (EBSD) technique.
Spark plasma sintered samples show MWCNT agglomerations along particle boundaries throughout the matrix surface (fig. 4), whereas in hot coining sintered at 600°c temperature for 1.5 hours followed by pressing/coining MWCNT embedded in matrix grains and it is not moving towards grain boundaries (fig. 5).
M,[3] reported that during the compaction, particle rearrangement and particle sliding occurs and results in increased number of particle contact.
Schematic representation of MWCNT distribution after sintering in (a) SPS and (b) hot coined samples Grain boundary clustering hinders the neck formation between adjacent matrix particle during sintering, resulting in poor densification and porosity.

Fig. 2 XRD pattern of three samples The scherrer formula was used to calculate the grain size.
The grain size of TiO2 was increased obviously, from 32.51 nm to 62.70 nm, and that of Na2Ti6O13 was from 31.49 nm to 37.80 nm.
Li et al has found that the grain size will be smaller in higher detonation velocity[12].
Table 1 The grain size calculated by Scherrer formula No.
From fig. 3(a), it can be seen that sample T1 was irregular spherical, or even sheet, with a small number of regular spherical particles.

Using the shaker device grain size reduction and the mechanically induced formation and thermal stability of wüstite was observed.
However, using the planetary device only grain size reduction was observed without chemical reaction to form wüstite.
In this analysis the single line profile is related to the volume averaged column length DV normal to the reflecting planes and microstrain along the same direction assuming isotropic grain shape and disorder.
Journal Title and Volume Number (to be inserted by the publisher) 3 pure metals, resulting in a lower annihilation rate of defects during the initial stages of the grain refinement [4].
Using a planetary mill for 50 hours, the formation of wüstite is not observed even if the grain refinement is similar to that obtained after 2 hours using the SPEX.

The experimental environment and grain model are all cylinders, as shown in Fig. 2.
The cloud picture of the surface temperature of the grain is shown in Fig. 3.
Overall temperature of grain Figure 4.
Grain center surface temperature Figure 3.
Number of temperature measuring three points as shown in Fig. 5.