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The structure of these composites was compact; a TiN phase was uniformly distributed between cBN grains.
The hardness of the investigated samples was dependent on the volume and grain size of the binding phase.
Their unique properties are rrelated to grain sizes of a few nanometers.
With small grain sizes, an appreciable fraction of the atoms reside in grain boundaries, i.e. atoms are situated in defect environments [4].
The VCS algorithm is one of the most powerful tools for calculating chemical equilibria especially for systems with a large number of condensed phases.

The present study evaluated the mechanical properties in compression parallel to grain of five pieces of wood from the roof structure of a residence undergo the fire in the rural area of Itapeva/SP.
Temperature (oC) Fig. 1 Strength in compression parallel to the grain.
Fig. 2 Different profiles of specimens obtained for parallel compression to grain test.
Because of it is a case study, we indicate the continuation of researches in this investigation line with a larger number of specimens, and also with other wood species, in a laboratory with continuous control of the experiment, as well as the chemical and thermal gravimetric analysis of wood after the same suffers a high temperature test.
Zhao: Compression strength and modulus of elasticity parallel to grain of oak wood at ultra-low and high temperatures.

It is interesting to notice that the grains with different orientations show different growth rates.
Grains with random orientations have much larger growth rates than any other texture components.
At the early stage (Fig. 2a), there are more nuclei or new grains (larger sizes) with random orientations (grey grains on the EBSD maps).
These randomly oriented grains grow faster, leading to an increased volume fraction of grains with random orientations.
Acknowledgements The authors would like to acknowledge the financial support from National Science Foundation of China (NSFC) under the contract number of 51171214 and 51001016.

Because of shallow groundwater level, it was easy to rise to the surface above the elevation after coal mining and result in a large number of high quality cultivated land perennial water [3, 4].
Due to the lack of filling materials, farmland with subsidence depth and perennial water was difficult to recovery grain production through reclamation technology, the recovery rate of farmland was in 50% to 70% and caused cultivated land area decreased 1/3 nearly [5-7].
The study area is an important production, processing and supply base for grain, cotton, oil and other agricultural products because it produced a number of grain accounted for 34.28% of the nation with 28.60% of the national arable land, so it has played a significant role in the protection of national food security.
At present, the reduction of cultivated land has been reached to more than 30 × 104ha, the economic cost of food and cash crops reached highly to 6 billion yuan per year, reduction of arable land area reached to 17 × 104ha with economic cost of 8 billion yuan per year, and that number increased year by year.
The recovery rate of cultivated land in governance subsidence was between 50% and 70%, and because of the reclamation of non-governance subsidence land was more difficult, so they usually used as water, and then resulted in a large number of farmland area reduced, and the unprecedented pressure on cultivated land protection.

When examining welded joints, the microhardness method is used, which makes it possible to obtain a large number of indentations in individual zones of welded joints, obtaining statistically reliable data.
At the same time, the lower microhardness of cast steel 245-260 correlates with a coarser grain size (≥ 500 μm) and a lower yield strength of cast austenite nitrogen.
The nitrogen concentration in the fusion zone is high, and the grain size is minimal in comparison with all other zones of welded joints of rolled products.
In the heat-affected zone of the weld metal at welded joints of cast steel, the microhardness also correlates with the grain size, i.e. does not change.
Unlike welded joints of rolled products, welded joints of cast steel have a grain size in the fusion zone that is not the minimum of all zones; the smallest grain size is in the weld metal.

To date, Mg alloys have been significantly inhibited by their low formability resulted from the hexagonally close-packed crystal structure and insufficient number of slip system.
SDC is independent of grain size, and allows low-cost superplasticity when compared to GBS[5].
After static recrystallization during 2-hour annealing treatment at 430˚C, as shown in Fig. 1 (b), equiaxed grains were well developed with an average grain size of d = 16 mm, which is larger than the typically required grain size of d < 10 mm for grain boundary sliding superplasticity.
Fig. 4 (b) and (c) show the coarse grains and uneven grain distribution near the fracture, resulted from dynamic recrystallization and grain growth.
The coarse grains and the cavities caused the premature failure of the material.

The failure requires necessarily local plastic strains where the number of cy-cles until fracture will be the lower the higher the plastic strain amplitude is ("low-cycle-fatigue").
S355 (220 HV) HAZ - fine grain S355 (220 HV) HAZ - coarse grain S355 (350 HV) HAZ - coarse grain S355 (350 HV) V-weld specimen local temperature Profile simulation specimen controlled resistance heating measurement homogeneous grain structure and hardness Base material S355 (180 HV) Base material S355 (180 HV) Base material S355 (180 HV) Base material S355 (180 HV) III Weld seam HAZ ∆UTh Weld seam HAZ ∆UTh T1 t Ac3 T2 T1 t Ac3 T1 t Ac3 T2T2 HAZ - fine grain S355 (220 HV) HAZ - fine grain S355 (220 HV) HAZ - fine grain S355 (220 HV) HAZ - fine grain S355 (220 HV) HAZ - coarse grain S355 (350 HV) HAZ - coarse grain S355 (350 HV) HAZ - coarse grain S355 (350 HV) HAZ - coarse grain S355 (350 HV) V-weld specimen local temperature Profile simulation specimen controlled resistance heating measurement homogeneous grain structure and hardness Figure 6: Welding simulation procedure [7,8] had been measured during
The calculated (NCM) and the observed (NC) remaining number of cycles are both referred to the number of cycles until crack initation.
Base material (left), simulated fine grain (220 HV, right) [7,9].
The method is not yet working with the same quality without any dependency on the grain structure.

The idea of SMAT is to introduce a large number of defects and/or interface into the surface layer by plastic deformation, which is realized by the repeatedly impacting of flying balls to the material surface.
The accumulation of plastic strain and the increasing of strain rate along the depth from the deep matrix to the top surface of the treated material will gradually refine the original coarse grains into ultra-fine grains (ufg) and/or nanometer-sized grains.
The grain size of the top surface can be refined into nanometer range, with an average grain size of a few nanometer to tens of nanometer (Table 1), which may vary with materials [6-13].
Generally, dislocation activity and twining will intertwine each other during the deformation process and will generate various configurations of dislocation arrangement (e.g. dislocation walls, tangles, arrays, etc.) or twins to subdivide the original coarse grains into sub-grains or cells which will finally be divided into nanometer-scaled grains.
Variation of the COF with the number of cycle for the SMAT Cu and the CG Cu samples against a WC-Co ball in mineral oil under the given test parameters: normal load of 50 N, frequency of 20 Hz, slip amplitude of 50 µm and fretting cycle of 72000.

The abrasive grain block is composed of diamond grain and thin.
Fig.4 show the effects of the diameter of the abrasive grain block on the packing density of abrasive grain block.
It can be seen that the packing density of abrasive grain block increase with the diameter of abrasive grain block and the width of the groove will decrease.
Arrangements of the abrasive grain blocks with different k value when abrasive grain block diameter D= 0.8mm Fig.4.
Increasing the abrasive grain block diameter D and decreasing the phyllotactic coefficient k can increase the distributing density of the abrasive grain blocks

There were both equiaxed and elongated grain, which average grain size of was 18μm.
The second phase not only pinned on the grain boundary, but also in the grain.
The grain was elongated obviously.
The elements which has High z number must exist in this phase due to it was brighter and bigger than other two phases shown in Fig.4 (e).
Both of the two elements were rich in the grain boundary to restrict the growth of grains.