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However, there were some precipitates which rich in Cu, Ag or Si in the grain boundary of the as-synthesized sample and the precipitates gradually reduced with the increase of annealing time.
It can also be seen that some black and white precipitate inlaying in the grain boundary.
The shown compositions of point A to C are normalized by assuming that the number of Cu+Ag+Si is 46.
The main phase of all the samples was Type-I clathrate and some transition metal rich or Si precipitates inlaying in the grain boundary.

Refining molten steel with argon blowing by metal nozzle mold bottom Shi Ronggang 1,a,Wang Zhanyong 2,b＊and Yang Sengai 3,c ,Yan Xiuping4,d 1,2,3,4Nuclear and Radiation Safety Center, 10082,China a ,c,d.srgsrg1990@126.com b zhanyong66@163.com Key words: die bottom blowing argon steel segregation Abstract: Abstract: this paper describes the main characteristics of bottom blowing argon, and by comparing forging adopting the mode of bottom blowing argon process of forging with not using the technology of forging the same time and the same kind of shape of ingot production the same in the forging crack, the results of the ultrasonic flaw detection, grain size, mechanical properties, gas content in liquid steel, the influence of the mold bottom blowing argon through the comparative analysis on the influence of the inclusions, the method of die bottom blowing argon can improve the quality of steel, It is worth promoting.
Figue 1 Refining process and number of defects exceeding the percentage of test object 3.2.1 In terms of testing brief look exceedances, vacuum casting flaw 42, exceeding the 29 defects, i.e. 69%; equal to 2/3 of the above products substandard; out of steel degassing flaw 86, defects exceeding 37, equal to 2 / 5 Product substandard; simulation of argon flaw detection 9, which is equal to 1/10 of product failure.
It is finished and the molten steel post without argon relevant. 3.3 mold bottom blowing on grain size and mechanical properties There is a trend of grain refinement.
Although the number of trials is not much, but we found a steel argon hydrogen content were lower than that in argon liquid steel, and because with the increasing amount of argon dehydrogenation rate increasing trend, see Table 4, when the average blowing the argon concentration of 51 liters per ton of steel, the average rate of 16.6% dehydrogenation.

In addition, nanotubes have the potential to act as filler within the cement grains, thus producing denser composites.
The 20- nanometer-thick (7.87 x 10'7 in.) semi-permeable surface layer allows water to enter the cement grain and leaches out calcium ions.
The silicate reacts with calcium ions to form a calcium-silicate hydrate gel, which binds cement grains together and sets the concrete.
A number of factors such as particle aggregation, rapid hydration, a high water to cement ratio, and the lack of gypsum can be hold responsible for this phenomenon.
Conclusions A number of developing countries have already launched nanotechnology initiatives to strengthen their capacity and sustain economic growth.

The collection time during electrospinning was controlled precisely to obtain a suitable (but not excessive) number (about 1,000) of aligned nanowires on the substrate.
An Optical laser microscope (OLS4000, Olympus, Japan) was used to capture the metallographic microscope image of the nanowires and to confirm the number of the nanowires on the substrate.
The surface of nanofibers looks smooth after calcination at 700°C, while it becomes rough above 800℃, which is probably due to the growth of grain with the increase of temperature.
On the other hand, the high conductivity of the nanofibers is also related to the large surface areas since the surfaces exhibit faster ion conduction compared to the grains and the grain boundaries.
Komem, The effect of grain size on the sensitivity of nanocrystalline metal-oxide gas sensors, J.

(b) TMZ (since grains have been upturned somewhat).
Observation of the intrinsic fracture features at the higher magnification revealed the grain boundary cracks to be surrounded by shallow dimples (Figure 19d) reminiscent of grain boundary ductile fracture.
The cracks propagated with ease along the recrystallized grain boundaries.
The weld nugget region revealed the occurrence of full dynamic recrystallization comprising very fine equiaxed grains. 2.
Cyclic fatigue fracture surface revealed isolated microscopic cracks covering the transgranular fracture region, cracking along the grain boundaries with numerous dimples adjacent to the grain boundary cracks reminiscent of locally brittle and ductile failure mechanisms.

The oxidation is started by introducing a constant number of oxygen molecules in the vaccum slab above the Al surface.
(a) Bulk polycrystalline aluminum sample composed of 16 grains with a mean diameter of 5 nm, which correspond to a total number of 62 969 atoms.
The grey light atoms correspond to the grains and the dark grey ones to the grain boundaries.
In these figures (Fig. 2a-b), the y-axis represents the evolution of the number of oxygen atoms in the oxide.
(1) (a) (c) (b) (d) Number of oxygen atoms Number of oxygen atoms Oxide film thickness (nm) Oxide film thickness (nm) Time (ns) Time (ns) Time (ns) Time (ns) (d) (b) In this expression, t is the oxidation time, �/S is the number of oxygen atoms per unit area in the oxide film, Kl and Klog respectively the linear and logarithmic constants.

Besides the grain boundary a, resulting acicular α phase was also present as isolated laths inside the grains or as Widmanstätten laths near prior β grain boundaries (Figure. 4(b)).
The latter may be related to b grain boundaries, caused by grain boundary alpha phase, is a typical feature of the intergranular brittle fracture.
Along grain boundaries, there are many mountains like tearing ridges.
They gradually spread into the grain, and divert like branches of a tree.
The α phase is located both at the prior β grain boundaries and within the β grains.

The recrystallization process is incomplete, as fine grains are only formed chain-like around coarser grains (see the arrows in Fig. 3).
The reason for the existence of the large grains can be discussed as follows: large grains probably arise, because few grains exhibit a prismatic orientation during TRC.
This leads to a hindered nucleation of recrystallized fine grains in particular areas resulting in larger grain size.
These large grains are mostly present in the sheet middle [6].
Acknowledgements The authors wish to acknowledge the financial support of the SMiLE project (“Systemintegrativer Multi-Material-Leichtbau für die Elektromobilität”, project number: 03X3041O) by the German Federal Ministry of Education and Research.

in which ρp is the density of the material points, representing the discretized material density ρ, Np is the total number of material points, Mp is the mass of a material point, Xp is the vector of material point position, v is the velocity vector, is the acceleration (dot denotes the time derivative), is the Cauchy stress tensor, and are the vectors of surface traction and body force respectively, is the spatial gradient of the shape function .
The large number of system d.o.f. will lead to a huge size of global stiffness matrix, which requires a considerable amount of computational effort to invert.
Anisotropic constitutive law is used as introduced in our previous publications [10] as: (4) (5) in which σij is a component of stress tensor σ, is the strain rate, σs is the sintering stress, D is the relative density, R is the grain size of the powder, Db is the effective diffusion coefficient, and are functions of pure principle strains, as given in [10], and η* is the dimensionless grain boundary viscosity of the powder.
As a numerical example, we use a fixed sintering stress and grain size σs = 1 MPa, R = 1 μm, the effective diffusion coefficient Db = 1.5×10-36 m5sN-1, and grain boundary viscosity η* = 0.005.
The number of material parameters required by the model is reasonable and can be obtained by comparing the simulation results to experimental studies.

This technologically important alloy is subject to manufacturing processes that impart a preferred orientation (PO) of the individual crystal grains within the material.
The orientation of the grains, or polycrystalline texture, can have a profound effect on the physical properties of a manufactured part, affecting both its strength and possible failure modes.
Moreover, the descriptions of crystallographic texture have been a part of the Rietveld refinement technique ever since the initial description of the method by Rietveld [3], who used a simple Gaussian model for grain orientations in ND data of many overlapping reflections and textured samples.
Subsequently, the GSH [4] approach of the ODF, which maps the probability of each of the possible grain orientations with respect to the external sample dimensions, involves a greater number of adjustable parameters for PO correction.
The neutron technique was used because it is able to measure complete pole-figure of the alloys investigated and provides high accuracy results, Journal Title and Volume Number (to be inserted by the publisher) which is necessary to see small differences in the degree of texture variation in each alloy.