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The number at the beginning of each series represents the main elements added to this aluminum alloy, while the following number of the series represents the specific aluminum alloy model, which can reflect the difference in the composition of the added elements, as shown in Figure 1.
This approach achieves the enhancement of alloy-specific strength by suppressing grain boundary (GB) mobility in nanocrystalline alloys.[10] Table 2.
Equal-channel angular pressing (ECAP) is a key technique, utilized to induce grain refinement through severe plastic deformation at elevated temperatures.
The gear fatigue testing results are shown as calculated tooth bending stress versus the number of cycles in Figure 23.
Maximum tooth bending stress against the number of cycles for the CFRP gears and the comparison with commonly used materials in polymer gear design [31].

The results in the third column of Table 2 present the effects of number of layers on flexural strength.
With the number of layers flexural strength decreases at first and reaches a minimum at 2, followed by a slight increase.
When the number of layers is 1, the flexural strength reaches the maximum.
In the process, the alumina grains block off a crack spread and lead to a crack defluxion or a crack increment.
The shapes include a large number of irregular polygons.

Its porous structure was characterized by a prevailing number of small micropores of similar dimensions, uniformly distributed in the material.
Chemical composition of the starting gel derived materials [mole %] The method of preparation of these materials, which were used as a starting materials for producing of porous sinters, is in detail described in earlier paper.[5] The obtained materials were in the form of heated gels of irregular, fine grains.
They were ground in a rotating- vibrating mill for 5 hours to obtain the sintering powders of grain fraction 2-4 µm.

Based on the concept of SAP, the whole creep curve can be represented by a set of small numbers of numerical parameters, and can be extrapolated from a part of creep curve [1].
The important parameters of creep characteristics are its stress dependence, grain size dependence and temperature dependence, which are characterized by the stress exponent, n, the grain size exponent, p, and the activation energy of creep, Qc.

The same trend is observed with post deposition heat treatment at 500˚C where phosphate bands and a carbonate band appear around the same wave number.
The trend of AFM images also shows nucleation and grain growth of the crystalline HA during the higher-temperature heat treatment.
These nano-sized HA structures could be more advantageous to bone cell adhesion and proliferation, as the presence of a higher number of grain boundaries would give better wettability in finer grains compared to micro sized HA [11].
(a) Apatites formation (b) (c) Figure 5 SEM images of HA coatings post deposition heat treatment for 2hrs at (a) 600 0C (b) 500 0C (c) 400 0C (d) 300 0C for 2 different magnification (ascending order left to right) after SBF 24hrs 2.XRD and FTIR analysis indicated characteristic peaks of HA and a transformation from amorphous to crystalline by post deposition annealing results in a crystalline structure at 600 0C. 3.SEM images showed that the microstructure of the hydroxyapatite coatings is homogenous. 4.AFM analysis suggested nucleation and grain growth of the crystalline HA during higher temperature heat treatment. 5.Examination of the SBF test indicated that post deposition heat treatment at 600 0C could activate interaction in the SBF within a short period of immersion, which in turn could accelerates the growth of the apatite layer showing good bioactivity on the surface.

The sharp peaks of MgB2 are indexed to the hexagonal crystal structure of ICDD file number 38-1369.
The sample show fine faceted hexagonal and randomly oriented MgB2 grains of varying sizes.
The grains have size varying around 1 m.
The EDS shows presence of Mg, B and traces of O in the grains, which is in agreement with the XRD results.
The maximum length of the wire prepared is about 5 m and the maximum number of filaments in multi filamentary wires is 10.

As it always happens at organization of such small conferences, it was originally decided to keep it as a workshop, and to narrow down the topics: only grain boundary diffusion, or only segregation or only stresses.
Nevertheless, we have tried to define some topics of the workshop such as: diffusion and stresses, diffusion and phase transformations, general problems of diffusion in condensed media, especially in polycrystals, grain boundary diffusion and grain boundary segregation, diffusion processes in nanostructures and in thin films, diffusion and related phenomena (sintering, intergranular brittleness, superplasticity, oxidation, etc.).
Besides he agreed to be the moderator of a free discussion on Wednesday, the 29th of May, starting from 4 p.m., some kind of "round table" of topics on the nature of segregation and mechanism of grain boundary wetting.
That is why the number of the oral reports was relatively small and each of the speakers has got 30 minutes.
Participation of such a great number of leading scientists from all over the world was very important to us, since we pay so much attention to widening of the world educational and scientific cooperation.

It was previously ascertained that the TWIP steel consists of fine grained austenite, with a grain size of about 4 µm (even if a small fraction of sub-micron-sized carbides may also be present), with evident bands in the rolling directions, and its hardness is 235 HV, whereas the DP steel consists of dispersed martensitic regions within a quasi-continuous ferritic matrix, with a ferrite grain size of about 8 µm, small fractions of bainite and retained austenite, and its hardness is 290 HV [15, 16].
Unbroken specimens are shown with filled symbols and number of repetitions.
Unbroken specimens are shown with filled symbols and number of repetitions.
LBW induces a much lower notch effect; therefore, LBW tensile behaviors are controlled by the different grain sizes and/or by the solidification flaws produced by welding.

High magnification analytical transmission electron microscopy (ATEM) has been used to examine degraded tube specimens and has revealed Pb within porous, nanocrystalline, degraded grain boundary oxides that were several nanometers wide.
The Alloy 600 tubing was received in a mill annealed (MA) condition, having a yield strength of 377 MPa and a grain size of ASTM 9.5.
The Alloy 690 tubing was received in a thermally treated (TT) condition, having a yield strength of 304 MP and a grain size of ASTM 6.6.
For each potential, the table shows the exposure time, the number of specimens that cracked and the number tested.
The penetrations were mostly single cracks with a few secondary cracks extending two or three grain boundaries beyond the main crack.

The process of 3DP was patented in 1994 under U.S. patent number 005340656 [6].
Figure 7 Effects of SWT and PT on Vickers Hardness Number Figure 8 Effects of SWT and WD on Vickers Hardness Number Figure 9 Effects of PT and WD on Vickers Hardness Number Table 6: Responses with respect to model Std.
The grain structure of aluminium alloy in Fig. 10, showing dendrites formed during solidification.
The increase of the dendrites leads to grain growth.
Dendrites of one color as shown in Fig. 14 form uniform grains.