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Its major advantages are lower processing temperatures, low (or no) volumes of glass forming grain boundary phases, reduced shrinkage and the potential for near-net-shape forming.
An endless number of combination of mechanical, chemical, electrical, and thermal properties can therefore be achieved (Table 2).
This material has an improved mechanical strength for mainly the following two reasons: at first there is less formation of glass phases at the grain boundaries and secondly at small Al2O3 grain size is achieved due to the oxidation reaction of Al.

The Fe2P structure can be viewed in a number of ways [2]; we believe that magnetic frustration plays a role, and from this perspective it is relevant that the Cr atoms are on a distorted Kagome lattice of corner-sharing triangles, while the iron atoms form a triangular lattice of ‘trimers’ [4].
We find that magnetization measurements are a good diagnostic of sample quality, while our resistivity data show that the low temperature power law of ρ(T) is robust, suggesting that it is unlikely to be caused by a minority phase, grain boundaries or disorder.
Is it possible that the non-metallic or non-Fermi-liquid power law is due to the existence of grain boundaries or traces of minority phase such as the pure iron impurity phase?
SEM measurements on one pure nonmagnetic sample did not find any grain boundaries, so we believe that these are not the reason for the unusual resistivity.

No clear sign of complete decohesion of graphite particles was observed, instead, partial decohesion of interface was observed in a relatively higher number of graphite particles.
Further, EBSD analysis was performed on the sample to estimate the influence of plastic deformation on grain orientations.
In the inverse pole figure (IPF) map (Fig. 3 (b)), gradient of the crystal orientation was clearly visualized within a grain.
The local crystal misorientations within grains were due to the severe plastic deformation of the ferrite matrix.

Nanocrystalline materials consist of a mixture of grains and the interface between those grains, called grain boundaries.
Though geothermal energy offers a number of advantages such as renewability, combustion-free, very low emissions, reduction in global warming and so on, but tapping geothermal sources for power has proven a tricky proposition, because of costs and hazards associated with deep drilling.

But through the study of isotope chronology, the U-Pb age of single-grain zircon is 2645±86Ma, the author suggest that the strata would belong to the late Archean.
The aggregate thickness is 1460.5m, the U-Pb age of single-grain zircon from amphibolite is 1620±160Ma.
The U-Pb age of single-grain zircon is 265.2±2.8Ma(Fig.6).
Acknowledgements This research is supported by Beareau of Geological exploration of Inner Mongolia(Project Numbers:NMKD2008-16).The authors are thankful to the chief engineer Fukuan Wang for his assistance in the field geological work.

A fully automated visualisation leads to computational tomographs of the system that can be coloured according to the identified wear particles (orange regions in the top panel), grain orientation in the style of EBSD imaging known from SEM micrographs, or vectorial plots that give an impression of the current shear strain rate in the near-surface region.
Inter. 9 (2017) 13713-13725. ], or the grain refinement and reorientation below the surface [[] S.J.
Experimental Simulation of Abrasion To evaluate materials regarding their suitability in abrasive applications, a number of abrasion tests are known [[] M.
Large-scale molecular dynamics simulations are well suited for studying fundamental microstructure-related phenomena like grain deformation, -refinement, rotation, and twin formation.

Fig. 1b) depends on the number of rolling passes as well as on the set of roll gaps.
The grains in the rarely deformed metal zone are coarser.
It can be caused by recrystallization and subsequent grain growth in the pre-profiled strip zone during the preliminary annealing.
The finer microstructure of the strained strip area consists of grains, which are elongated in the rolling direction.

Unit type of finite element is plane 42, and element number is 293722.
In these process parameters, austenitizing temperature and tempering temperature is both too high, so that not only cooled difficulty of flail knife in 42CrMo is increased and hardening degree after quenched is decreases, but also coarse grains is easily occurred in whole knife.
So that, the crystal grain at the point of mounting hole is much coarser and mechanical properties is worse than the other place of flail knife.
In older to prevent coarse grain, and to increase the harden degree after quenching, and not to shorten the service life, the suggestions for the manufacturing process is made.

Tests of oxidation resistance at temperature as low as 500 ℃ show that: the number of cracks of the composite coating (MoSi2-SiC or MoSi2-Si3N4) is smaller than that of the monolithic coating of MoSi2; its oxidation resistance at low temperature is enhanced obviously, which is achieved mainly by reducing the mismatch of thermal expansion coefficient between the composite coating and the Mo substrate, and the formation of highly volatile MoO3 [21, 22].
The addition of Al is beneficial in that when the composite was oxidated, Al2O3 will be produced at first place, whose volume expansion rate is much smaller than that of SiO2, which in turn reduce the negative effects brought about by the grain boundary glass phase of SiO2, and improve the high temperature strength of materials[24]
The addition of W and B elements has the function of refining grain and enhancing the room-temperature bending strength of materials[27].
Table2 Properties of samples Material Porosity Bending strength Micro-hardness Fracture toughness % MPa HV MPa·m1/2 MoSi2 2.9 160 1 341 2.52 10 %ZrO2-MoSi2 4.5 380 1 499 5.81 20 %SiC-MoSi2 2.7 215 1 912 3.84 (20 %ZrO2 + 10 %SiC)-MoSi2 4.1 470 1 975 7.65 In abroad, by comparing the high temperature performance of MoSi2 composites with different mole fraction of Mo5Si3 or WSi2, Schwarz[28] states that the addition of Mo5Si3 and WSi2 can increase the high-temperature bending strength of MoSi2 Matrix at temperature of 1200～1400℃ by 25 times, and the effect of solution treatment of WSi2 is more obvious than that of fine grain strengthening treatment of Mo5Si3.

The frictional force Pf between powder and dies of traditional single powder compaction process is reverse with the pressing direction, results the loss of pressing force P, the actual force P1 applying on powder green is less than the pressing force P, namely PP fP −=1 (1) When the powder compaction is made without friction, namely the ideal condition Pf=0, the actual force P2 applying on powder green is equal to the pressing force P, namely PP =2 (2) When the direction of frictional force Pf is same with the direction of pressing, the actual force pressing P3 on the powder green is more than the pressing force P, namely PP fP +=3 (3) This means that frictional force can be made of the part of pressing force to make displacement or deformation of powder grain, and can change the distribution
The total number of elements is 960, and the simulation model is shown in Fig.2.
The reason is that when pressing force is applying on the powder body during the compaction process, the plastic deform of powder grain is made, the internal stress - elastic stress- congregate in internal parts of powder grain, the direction of stress is reverse with outside force and resist deform of green.