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less extent of grain growth and particle agglomeration induced by high combustion temperature.
TNxC1-x is the solid solution of TiC and TiN, change of x value which refers to the atom number of N in a TNxC1-x cell leads to the change of the lattice parameter.
AdditionTiO2 dilution decreases the combustion temperature, prolong the tlow, and this is a limitation of grain grown since we know the nucleation process occur under low temperature, but the grain grown process occur under high temperature.
These conditions lead to high nucleation rate but low grain grown rate.
The larger particles were reasonable deduced to be formed in the first step from the Titanium carbonitride process because the resulted high local temperature facilitates its grain growth.

TEM observation revealed that the nano-sized SiC particles were mainly dispersed within the matrix grains.
Most of nano- SiC particles were present inside Al2O3 grains and only a few particles located at the boundaries or at the junctions of grains.
When the grain boundary movement of Al2O3 came into contact with nano-sized SiC particle with high surface energy, it would went over SiC particle and enwrapped it.
For the same volumetric fraction of SiC, the number of particles in the present phase was about 2orders magnitude higher than in the materials found in literature.
The SiC particles retarded the densification mechanisms by hindering the grain boundary movement.

The studies have been reported in past to design the risers in casting based upon shape factor The number of slurry layers basically defines the ceramic shell mould thickness [5].
More the number of slurry layers more will be the thickness of shell [1].
Figure 7), but with slightly smaller grains as compared to exp.no.6 hence hardness of 240HV is obtained.
This is because of uniformly distributed pearlitic-ferritic microstructure with larger grain size (Ref.
While in exp.no.2 hardness is slightly less i.e. 166HV, having non uniformly distributed pearlitic-ferritic microstructure with variable grain size and inter-dendrite segregation and further in exp.no.5, hardness is minimum 156HV due to smaller grains.

Crushing of the brittle materials grains can be achieved by shock loading.
These phenomena are used for producing materials of micro- and nanoscale grains.
Compaction of such materials by shock waves has the advantage that during the compaction phase grain growth does not occur.
Shock loading leads to intense fracturing of the initial grains and stacking, leading to void decrease and to consolidation
Nowadays, the annual number of prosthesis replacements of hip-joints has increased to about 300 000 in the USA, 60 000 in Germany and 20 000 in Russia.

Introduction While the asphalt pavement with its unique advantages in road construction played an important role and has been widely used, it also faces a number of diseases related temperatures, such as high-temperature rutting, translation, and low-temperature icing and cracking etc.
Silica sol, the content of SiO2 is 30%, pH is about 9.9, grain size is about 11.7nm, from Zhenjiang Yuda Chemical Co., Ltd.
Thermal physical parameters of asphalt-SSPCM blends PEG content / WPEG (%) 47.6 57.1 66.7 76.1 Physical presentation fine grain fine grain fine grain fine grain The onset temperature/ Ton (°C) 44.2 44.4 44.6 44.7 The peak temperature / Tp (°C) 57.5 60.7 62.6 63.4 The endset temperature/ Tend (°C) 85.1 89.0 94.2 95.3 Phase change enthalpy / ΔHm (J/g) 38.2 65.5 91.0 117.5 Theoretic enthalpy / ΔH (J/g) 89.5 107.4 125.3 143.2 Enthalpy loss rate /ΔHloss (%) 57.3 39.0 27.4 17.9 Mass loss rate /Mloss (%) 0.10 0.16 0.17 0.03 In asphalt-SSPCM blends, PEG acts as a phase change materials for heat storage.
After heating Before heating Fig.1 The appearance pictures of blends before and after heating Fig.1 shows that blends are fine grain and still maintain stable shape after heating, fine grains as independent heat storage unit have good dispersibility.
In contrast, in winter, the asphalt pavement with SSPCM can reduce the number of freezing situations or even to mitigate the risk of differential rime frosting.

In the transverse sections of the cylindrical Sample 1 one can see curled Nb ribbons bending around the relatively coarse Cu grains (Fig. 3a, b).
The Cu grains are coarse, the sizes of 200-300 nm, they have polyhedral shape and low dislocation density.
Nb grains possess a relatively high dislocation density, the dislocations concentrating mainly in fine blocks the size of about 10 nm (Fig. 4e).
The third stage corresponds to the growth of the recrystallized grains.
The Nb filaments still have mainly the ribbon-like shape and are curved around Cu grains (Fig. 5a).

The samples with coarse grain sizes (N3 and N4) show crystalline phase structure after milling.
As the amount of powder in this study was not varied, the number of impacts at certain speed of milling can be assumed to be directly related to the number of balls in the vessel.
Additionally, the number of impacts is influenced by milling time and speed of rotation.
The smallest particle size, 1.2 mm, was obtained for the highest number of impacts.
(4)Number of impacts is in correlation with average particle size.

It was showed the influence of the solution temperature in range of 875 to 975°C on the number, size and distribution of carbides in pure titanium with content of 0.2 wt. % carbon and on the hardness test of researched alloys.
Research results In the microstructure of technically pure titanium with C content of 0.2 wt. %, the recrystallised a phase grains (Fig. 1a) with mean area equal to 58.42±45 µm² are clearly visible.
At 900°C, it only exists in the form of few areas distributed at the interface and along grain boundaries.
Szkliniarz, Effect of cyclic heat treatment parameters on the grain refinement of Ti-48Al-2Cr-2Nb alloy, Mater.

In magnesium alloys, grain boundary sliding is caused by the following: 1).
Microstructural situation near the grain boundary.
The big grains are normally beneficial for the improvement of creep properties by delaying the grain boundary sliding.
The addition of trace amount of Cu in AZ91 alloy increases the number of precipitates in the matrix by a factor of ten.
The effects of matrix, precipitate structure, grain boundary and grain size on how to improve the creep properties were discussed.

., twins, secondary twins, elongated grains, and also high dislocation density as well [4, 5].
Table 1 shows the results of maximal stress – failure cycle numbers of pre-compressive strained samples.
The interfaces among twin bands and grain boundaries would be the barriers of the crack propagation.
The tensile plastic deformation makes denser twins and elongated grains, so that the fracture surface looks shivering, with comparing Figs. 6 b and d).
The crack propagates preferentially along twin band interfaces and grains. 3.