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The interaction mechanism among the dislocations, particles and grain boundaries is important with regards to the view properties of the material.
Failure life is defined as the number of cycles at which a 10% drop from the maximum value occurs in either the tensile or the shear stress values.
For circular, square and diamond path loadings, the maximum peak stress increases rapidly at a small number of fatigue cycles (about 50 to 80 cycles).
The existence of precipitates in Al matrix will hinder the dislocation movement in grains or between dislocation bands, which can be appreciated from Fig.3(a), and Fig.4(a).
As a result, the individual dendrite cell is isolated by thick eutectic walls, and it behaves as an individual dendrite grain.

This information is important as grain boundaries act as weak superconducting links in most high temperature superconductor materials [4,5], and models of current percolation at present assume a random (uncorrelated) distribution of the fibre texture orientations.
plate number A B C D Automated EBSP indexing of the Bi2223 phase One problem in the use of EBSP analysis for study of Bi2223 is that several different unit-cells have been postulated for this phase.
It is seen that most of the grains (88% by area fraction) lie with the crystal direction normal to the tape surface aligned within 10° of [001], confirming previous X-ray data that a strong fibre texture is developed in this material.
Such a procedure is sometimes referred to as either relative grain reconstruction or as a connectivity analysis.
Acknowledgements This work was supported by the National Natural Science Foundation of China under contract numbers 50474087 and 50231030.

Quasi-static loading tests were made at CTU, Experimental Centre of Faculty of Civil Engineering, Prague and we were used the same number of specimens as we used for the impact loading test.
For HPC specimens we used the similar fine-grained mixture as [13].
New model was exported to the text file with spatial coordinates X,Y,Z with 150000-300000 lines which equal to the number of scanned points.
These results can be explained by different homogeneity of both materials which high-performance concrete is very homogeneous in the terms of grain size.
For quasi-static loadings the crack passed through the weakest zones and around the aggregates (contact matrix and grains of aggregates).

As we could be seen from figure 2, with power increasing, the number of dendritic titanium carbide increased, the number of irregular shaped titanium carbide reduced, and the length of dendrite increased.
The unmelted titanium carbide particles agglomerate to form the coarse grain.
As power increased, the number of dendrites increased, granulated and oversized titanium carbide become less and less.
We can be seen from the figure 5, along with the increase of scanning speed, the cladding layer obtained energy reduced, titanium carbide was easy to agglomerate to form a coarse grain.
Titanium carbide grain in picture c d was in large size, the main reason was the scanning speed was too fast, cladding layer get less energy, few titanium carbide was dissolved, titanium carbide agglomerated easily.

Granularity as the name suggests is to take different sizes objects, or divides one ‘coarse-grained’ object into several ‘fine-grained’ objects, or combines several ‘fine-grained’ objects into one ‘coarse-grained’ object, then implement the study based on these granularity levels [7].
In this table, numeral ‘1’ indicates strong coupling, number ‘2’ represents the normal coupling, and number ‘3’ indicates a weak coupling.
The numbers in the Fig. 3 are the conduction strips inside rotor, which are interconnected at their ends.

And the fully α column grain growing from the edge to the centre was produced by controlling the cooling condition.
The subsequent heat treatment did not disturb the structural characteristic of the directional lamellar microstructure except for a small volume fraction (<5%) of equiaxed gamma grains with the grain size of 30~50μm distributed on the colony boundary (Fig.1b).
Up to date, there were a number of reports about effect of the thermal exposure on RT ductility of gamma TiAl alloy.
a Growth direction of column grain b B A Fig. 3 Fracture surface of the unexposed specimen with the directional lamellar microstructure.
Its mechanism is that micro-crack initially yields in the surface brittle layer during loading, which then leads to a number of small cracks running in the substrate.

By increasing the number of nuclei, very fine and uniform globular microstructures can be obtained, resulting in an increase of mechanical properties.
The most important things for the commercialization of the rheocasting process are to improve the quality of metallic slurry, such as obtaining fine and uniform grain size, to shorten the process time for manufacturing the metallic slurry leading to an increase of productivity, to decrease the production cost, and to improve the mechanical properties.
The H-NCM(Hong-NanoCasting Method) System If the nucleation density increases in the beginning stage of solidification, the primary α phase can easily grow into the globular shape with much finer grain size even under much faster cooling rates.
If we can increase the number of the nucleation density to N=15, such as for H-NCM, very fine and uniform globular microstructures compared to the case of N=1 will be obtained.
If we can increase the number of nucleation density up to N=1000, much finer globular microstructures, such as below 10 �, will be obtained, even at much faster cooling rates of 5°C/sec~10°C/sec.

The Use of Power Monitoring and Electron Microscopy in Evaluating the Performance and Fracture Characteristics of Abrasive Grains Jeffrey Badger1,3,a*, Radovan Drazumeric2,3,b and Peter Krajnik2,3,c 1The Grinding Doc, 82 Jane Street, #5B, New York, NY 10014, USA 2Univerisity of Ljubljana, Faculty of Mechanical Engineering, Askerceva 6, Ljubljana, Slovenia 3The International Grinding Institute, 127 W. 83rd St., #424, New York, NY 10024, USA ajeffrey.badger@grindinginstitute.com, bradovan.drazumeric@fs.uni-lj.si, cpeter.krajnik@fs.uni-lj.si Keywords: Abrasives, sintered abrasive, engineered-shape abrasive, fracture, chip-formation, electron microscopy.
The use of electron microscopy and power-monitoring during grinding was investigated in terms of evaluating the fracture and wear characteristics and chip-formation mechanisms of abrasive grains and bond formulations.
If that wheel is grinding at a wheel speed of vs=50 m/s and has a width of bs=25 mm, we can use the equation for the number of abrasive interactions per second, Na, given as: Na = vs · bs · C (1) to obtain Na=11.6 million abrasive contacts per second.
However, if the Aggressiveness Number, Aggrg, is chosen correctly, the power rise will not be rapid and drastic, as show in Figure 3.

Effect of Nickel-Modified SiC Particles on Compressive Damage of SiCp / 7075 Composites Xiaohong Wang1,a, Qiaogang Hu1,b, Shiyu Zhong1,c, Teng Dang1,d, Hailun Wang1,e and Yuanhua Lin1,f 1Department of Materials Science and Engineering, Southwest Petroleum University, Chengdu 610500, China axhwang3368@swpu.edu.cn, b1261253269@qq.com, c727693583@qq.com, d617518019@qq.com, e386160742@qq.com, fyhlin28@163.com Keywords: nickel-plating modification; silicon carbide particles; compressive damage; grain size; grain morphology Abstract.
For the aluminum-based composite material whose particles are polygonal, as the number of particles increases, the average force of the particles gradually decreases.
Table 2 Number of meshes Minimum mesh size / mm Size ratio Number of grids Matrix 0.00025 4 100924 Granule 0.00025 2 34748 interface 0.00025 2 56252 Study on the Geometric Model and Meshing of the Effect of Nickel-Modified Silicon Carbide Particle Morphology on Compressive Damage of Composites.
Table 4 Number of base and particle meshes Particle morphology Minimum mesh size / mm Size ratio Number of grids Matrix Sphere 0.0002 6 78636 Cube 0.0002 6 81520 Cylinder (D: H = 1:1) 0.0002 6 80564 Granule Sphere 0.0002 2 24128 Cube 0.0002 2 24924 Cylinder (D: H = 1:1) 0.0002 2 24684 Study on the Geometric Model and Mesh Division of the Effect of Nickel-Plated Modified Silicon Carbide Particle Size on Composite Compression Damage.
Table 6 Number of base and particle meshes Particle size / μm Minimum mesh size / mm Size ratio Number of grids Matrix 15 0.0005 2 32000 20 0.0008 2 47776 25 0.0008 2 74804 Granule 15 0.0003 2 24128 20 0.0005 2 15432 25 0.0004 2 37728 Material Model.

Cell number and cell activity (WST) were tested over a period of 3 to 13 days.
Infiltration of farringtonite with PLGA approximately doubled cell number compared to pure farringtonite.
As expected, pore diameter decreased with ppi number.
From SEM images (Fig. 3) a changed grain morphology can be observed at the surface of the struts.
In farringtonite foams microstructure is fine grained with some intergranular porosity.