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The microstructure of as-cast Inconel713Csuperalloy is composed of γ´precipitates in γ dendrite matrix with carbides along dendrite arm or grain boundaries and the eutectic γ-γ´phase[1].
In superalloys, grain boundary strength at the elevated temperature is increased by precipitation of the carbides.
(b) shows an interdendritic MC carbide at grain boundary.
Addtionally, as a result of EDS with point analysisshown in Fig.3, Nb-rich phase (NbC) was observed at grain boundary.
Acknowledgements Financial support by KIAT(Korea Institute for Advancement of Technology) grant number R0001377 and LINC(Leaders in Industrial University Cooperation of Korea research foundation)grant number L1-G05 are gratefully acknowledged.

Every yeah, a large number of economic loss and threat to life safety occur because of erosion, therefore, to study the erosion mechanism and develop wear-resistant materials are of great significance.
Table 3 Compositions of the enamel coating [wt%] Enamels A Enamels B Antimony trioxide Barium molybdate Sodium nitrite Borax Clay 30.8 60.6 0.8 0.8 0.4 0.6 6 2.3 Erosion tests Erosion method: Used air compressor as drive device, and made the abrasive grains streaming from the nozzle of it, and then the abrasive grains constantly impact on the surface of the samples to produce wear.
Test conditions: Kept the rate of abrasive grain stream at 20m/s by holding air pressure at 15Mpa, and the impact angle was 45°, and the grains’ particle size was between 40 and 80 mesh.
Fig. 4 (a) is the micro-morphology of enamel coating surface, and a number of long and deep scratches and potholes could be seen here.
The reason why there’re so many scratches is that the abrasive grains has angular, and if under a great impact velocities, the angular grains would cause the coating surface worn seriously, leaving many tiny chips behind, these chips are easily broken and dropping off during the erosion process, that’s one of the main reasons causing abrasion.

The abrasive diamond grain should be the same size as the Sic grain being used in loose-abrasive wire sawing.
The thickness of the bonding layer was set at 30 µm, considering this grain size.
In the manufacturing process, diamond grains are first stirred into liquid resin.
Hodsden: US Patent Number 6065462. (2000) [19] J.
Hodsden: US Patent Number 6,279,564.(2001) [20] T.

A great number of works were devoted to the increase of the field effect mobility and the stability of the off-current.
When using 100 to 200 nm thick amorphous silicon film, as with previous excimer laser crystallization experiments [4], some damage can be introduced at the SiO2 thermal barrier - a-Si interface resulting in great number of seeds and then in smaller grain size.
The optimum thickness, leading to largest grains, is found to be 400 nm.
Large grain size, similar to that obtained in the optimized conditions, is also obtained.
These areas are surrounded by elongated smaller grains originating from the colder rim.

A large number of coal gangue was accumulated on the surface of earth, which not only encroaches land but also pollutes the environment.
The corresponding samples were sequentially numbered for BGA1 and BGA2.
It exhibited that it was difficult to observe columnar mullite grains when the sample BGA2 sintered at 1350 °C-1400 °C.
As the sintering temperature rose, the grains grew and developed gradually as shown in Fig. 3(d) and Fig. 3(e).
When the sample BGA2 sintered at 1600 °C, the edge of grains presented molten state, then melted together with the surrounding grains.

However, the engineering and optimization of solid bonding processes is difficult and requires a large number of time and cost consuming test trials.
It is known that maintaining the metal to the melting temperature causes grain growth, and, consequently, an increase of the grain boundaries, which represents an energetic barrier.
· Heat capacity equal to 2.43 J·K-1 · Young’ modulus equal to 68947 N·mm-2; · Poisson’s number equal to 0.3; · Coefficient of thermal expansion equal to 2.2·10-5 Regarding the contact between the two objects, a shear model was considered.
Minamino, Strength and ductility of ultrafine grained aluminum and iron produced by ARB and annealing, Scrip.
Minamino, ARB (Accumulative Roll-Bonding) and other new Techniques to Produce Bulk Ultrafine Grained Materials, Adv.

Moreover the fracture is intergranular; the number and area of voids increases linearly with the total strain [4,10] and with the amount of sliding [3-11].
There are voids only when there is grain boundary sliding, but they are less likely to form when the grain boundaries can migrate.
When the thickness of the elongating grains declines below twice the subgrain size, some serrations on opposite GB of grains meet, pinching off grains to make them shorter and the neighbors at those points thicker.
Here the hard phase diminishes the DRV to some degree by reducing the freedom of glide of dislocations or by increasing the generation rate and the number of systems operating.
These particles are usually few in number but may be quite large (<100 µm).

To overcome its' inherently low coupling a number of approaches have been used.
This approach offers a number of opportunities.
This results in longer sintering periods and hence more opportunity for grain growth.
Whilst the use of microwaves does permit significantly finer grain sizes to be retained (Fig. 6), a lot more work needs to be done if grain sizes <100 nm are to be achieved via pressureless sintering techniques.
Average grain size ~140 nm.

These materials vary in chemical composition, density, grain size, thermal physical properties and microstructure [5,6].
The natural graphite and anthracite have a metallic surface with small pores inside the grains.
The letter denotes the carburizer type while the number denotes the material supplier.
During the examinations such parameters as the number of Fig.1.
The graphite precipitations number counted during melts analysis Fig. 4.

The authors gratefully acknowledge the National Science Foundation for financial support (grant number DMR-0206826) and Dr.
The grains are oriented along the rolling direction.
Increasing the rolling strain results in grain refinement in the rolled sample, which leads to an increase in the number of grain boundaries.
The increased grain boundary area can enhance diffusivity.
Acoff: Ultrafine Grained Materials III, (TMS Warrendale, PA 2004), p.381