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It was found that the grain size and its distribution influence the property and microstructure of Si3N4 ceramics, namely, the relative narrow distribution of grain diameter in some extent and relative wide range of bimodal distribution of grain aspect ratio could improve the property of Si3N4 ceramics.
Minimums of 300 grains in each material were analyzed.
In these micrographs, the β-Si3N4 grains are observed clearly.
The addition amount of rare earth oxide, the heat-treatment temperature and the atomic number of rare earth element have key effect on the α→β transformation ratio of Si3N4 powder.
The grain-section diameter dominated the fracture toughness.

The results show that the specimens have uneven microstructure, and the grains are relatively small.
The grains grow mainly by the form of columnar and cluster-like, and there are obviously preferred orientation in the (220) plane.
Grain size: Considering the diffraction peak broadening caused by the grain size, the relationship between grain size D and the width of its real point β can be given by Scherrer formula: D (h k l) =k λ/β cos θ
Grain size of each small columnar is about 5μm.
Since the whole grain is in equilibrium, when the LIGA Ni micro-structure only exist micro-stress, the grain in a certain part is tensile stress, while the other part is the compressive stress.

The conventional Ti-6Al-4V had a grain diameter of 8 - 10 µm, whereas the fine grain had a grain diameter of 0.8 - 2.0 µm.
Fine Grain Ti-6Al-4V sample preparation conditions.
Alpha case thicknesses for (a) Superplastically Formed conventional grain and (b) as-exposed fine grain Ti-6Al-4V materials.
Depth of removal as a function of traverse rate for (a) Conventional Grain and (b) Fine Grain specimens.
[8] Hashish, M., et al, "Method and Apparatus for Fluidjet Formation, US patent number 6280302, August 2001

The cementing strength between the adhering sand casing and the interface of cement mantle is related to sand grain diameter, distribution density and the thickness of adhering sand agent, the in-house experiments could be instructed by designing orthogonal experiment scheme, according to which the laboratory findings could be analyzed by gray correlative method.
A is the grain diameter of sand, A1 is 2mm sand, A2 is 4mm sand, A3 is 6mm sand, A4 is 8mm sand; B is the distribution density of sand, B1 is 50%, B2 is 70%, B3 is 80%, B4 is 90%; C is the thickness of adhering sand agent, C1 is 1mm, C2 is 2 mm, C3 is 3mm, C4 is 4mm.
Table 1 The design scheme of orthogonal experiment Horizontal effects The order number of experiment A1 A1B1C1 A1B2C2 A1B3C3 A1B4C4 A2 A2B1C2 A2B2C1 A2B3C4 A2B4C3 A3 A3B1C3 A3B2C4 A3B3C1 A3B4C2 A4 A4B1C4 A4B2C3 A4B3C2 A4B4C1 2.
However, the number of correlative coefficients is large, the information is too dispersive and not convenient to be compared, thus, to calculate the average value for the correlative coefficients and synthesize it to be a vector
According to the calculation result of degree of association: , the influence of sand grain diameter on the cementing strength is largest, then the thickness of adhering sand agent is second, and the influence of distribution density of sand on the cementing strength is least. 3.

Wetting of nanoparticles by liquid aluminium presents a number of challenges.
A number of techniques have been used to incorporate nanoparticles into molten aluminium.
Grain refining was accomplished using 5TiB master alloy to achieve a level of 40 ppm B in the melt.
Most particles and particle clusters remained at the grain boundaries.
Conventional grain refining improved tensile, yield and elongation values.

In addition, the original fine grains and continuously refined grains can enhance the strength by restricting the growth of grains and motion of dislocations.
In addition, it shows that the grain size of samples is not very small (fine grain of ~20 μm and coarse grain of ~50μm).
It can be seen that the grain structure was inhomogeneous and mainly consists of relatively fine equiaxial grains of ~20 μm and coarse grains ~50 μm.
Fig. 3d, e and f (i.e. elongation of 15%, elongation of 24%, fracture, respectively), obviously, the grains were stretched, and the number of twins increases gradually.
At the same time, many fine equiaxed grains around coarse original grains.

The optical band gap was found to be varying with annealing temperature due to removal of defects and increase in grain size.
It was also observed by the X-ray diffraction pattern the grain size of the film increase with annealing temperature.
However peaks found in XRD is due to annealing effects that reduced the defects and increase the grain size of film.
In our case, Increase in grain size that was confirmed by our XRD measurements.
In as deposited films the peak of Zn found to be at channel number 580 and for Se at channel number 610 as our earlier studies [7] but after annealing peaks is found to shifted with annealing temperature.

The material was recrystallised containing equiaxed grains with an average grain size of 80 ± 12 µm.
Results Microbands were observed in 41 grains after forward/forward (F/F) torsion and 60 grains after forward/reverse (F/R) torsion.
The analysed grains mostly displayed either one or two sets of microbands with a few grains exhibiting three sets of microbands.
An example grain of the F/F material is shown in Fig. 2.
that in absolute numbers (not relative frequency) there were significantly more boundaries with misorientation between 2 and 15° for the F/F material, i.e. the microstructure was far more heterogeneous.

The result showed an insignificant difference between 0 and 90 degrees of grain direction in aramid composite in any properties.
Variables for each treatment were differentiated by the grain direction.
The results are shown in Table 1 that the samples with weft direction (90˚) have a higher number of compressive strength (193.71 MPa) than the ones with warp direction (203.61 MPa).
These numbers explain the reason why the compressive strength of warp direction samples was higher as well.
The samples were varied by their grain direction: warp (0˚) and weft (90˚) directions.

However, magnesium and its alloys show poor ductility due to the limited number of slip systems associated with the HCP crystal structure [1].
In order to understand the texture evolution in pure magnesium and magnesium alloys during deformation, a number of experimental and simulation studies have been conducted [2-4].
The specimens are annealed for 1h at 723K to produce a uniform grain structure.
attributed to the growth of the grains with (0001) orientation.
Thus the preferential growth of (001) oriented grains occurs, resulting in the development of (001) texture.