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The usual ways of improving the figure of merit include[2-4]: (a) Choosing the best concentration of carriers; (b) Improving the ratio of the Seebeck coefficient, and electrical conductivity; (c)Improving the grain orientation; (d) Nano-size thermoelectric materials.
Table 1 The thermal conductivity of samples at 250℃ and their density Test number Ethyl alcohol (ml) Ethylene glycol (ml) Citric acid (g) pH κ (W.m-1.k-1) Density （g/cm3） 1 80 1.4 10.76 3 0.911 3.014 2 80 2.6 12.11 4 1.143 3.307 3 80 3.8 13.45 5 1.25 3.299 4 80 5.0 14.9325 6 1.083 3.253 5 90 1.4 12.11 5 1.006 3.012 6 90 2.6 10.76 6 1.243 3.459 7 90 3.8 14.93 3 0.866 3.015 8 90 5.0 13.45 4 1.205 3.342 9 100 1.4 13.45 6 0.794 2.894 10 100 2.6 14.9325 5 1.195 3.181 11 100 3.8 10.76 4 1.126 3.245 12 100 5.0 12.11 3 0.888 3.132 13 110 1.4 14.9325 4 1.174 3.105 14 110 2.6 13.45 3 1.101 3.144 15 110 3.8 12.11 6 1.056 3.079 16 110 5.0 10.76 5 1.054 3.029 T1 4.387 3.885 4.334 3.766 T2 4.32 4.682 3.881 4.648 T3 4.003 4.298 4.35 4.505 T4 4.385 4.23 4.318 4.176 From the result of the table 1, the thermal conductivity is greatly affected by ethylene glycol and pH, but has a litter correlation to ethyl alcohol.
For sample 9, the particles present inhomogeneous character and some particles with large grain size exhibit lamellar structure.
The particles present lamellar structure with the grain size of 200 nm ~ 1.5 μm.
Thermoelectric properties of highly textured NaCo2O4 ceramics processed by the reactive templated grain growth (RTGG) method, J.

There are traces of turning process on the surfaces of the fragments of both shafts, a significant number of defects - burrs, nicks, as well as round-shaped defects in the form of pores and exogenous inclusions.
In the structure there is a transition from Widmanstatten (Fig. 8 b, f) to fine grain (Fig. 8 c, g); 3 - the core of the shaft.
The microstructure of the shaft #1 core (lamellar perlite with a different grain size from 5..6 to 2..3 points on a scale of 1 GOST 5639-82 with a ferrite network along grain boundaries) is typical for steel 45 after annealing [5, 6, 10] .
The increased sulfide content, non-optimal structure (Widmanstatten, coarse grain, ferrite network) led to a decrease in the metal resistance to shock loads and contributed to the development of fatigue cracks. 2.

The ferrite grain size of samples was measured using the planimetric procedure according to the ASTM-E112 standard.
Results and Discussion The intercritical annealing temperature, the ferrite grain size, the martensite content and its islands size for different DP samples are given in Table 2.
In this table, the numbers after A and B indicate the martensite content of steels.
The intercritical annealing temperatures, the ferrite grain size and the martensite content and its islands size for differnt DP samples.
Martensite Islands Size (µm) Martensite Content (%) Ferrite Grain Size (µm) T(°C) Steel Sample 5-10 11.1 18.4±0.4 730 A-11.1 7.5-14.5 26.4 18.4±0.4 761 A-26.4 7-12 12. 5 19±0.4 730 B-12.5 11-18 27.8 19±0.4 754 B-27.8 The variation of ln(dσ/dε) as a function of lnσ is plotted in Figure 3.

To ],1[( mkCak ∈∈∀ , m is the number of condition attribute.
Then the average recrystallization grain size can be obtained from the OM microstructures.
It can be seen that the change slope of grain size by strain rate(shown in Fig.5) is much smaller than by billet temperature(shown in Fig.6).
Fig.4 OM Microstructures of AZ80 alloy under different temperature and strain rate (a) T=300 ℃, ε� ＝10 s-1；(b) T=300 ℃, ε� ＝50 s-1；(c) T=350 ℃, ε� ＝10 s-1； (c) T=350 ℃, ε� ＝50 s-1；(e) T=450 ℃, ε� ＝10 s-1; (f) T=450 ℃, ε� ＝50 s-1 Fig.5 Grain size at 300℃、350℃、450℃ Fig.6 Grain size at 10s-1、50s-1 and different strain rate and different temperature (a) (b) (c) (d) (e) (f) Acknowledgement This work is partially supported by Guangdong Provincial Natural Science Foundation of China #9451806001002350 and Research Fund of International Cooperation Project of Science and Technology Ministry # 2008DFA50990.

As examples, numbers of step, high energy consumption, exposed to hazardous during handling molten metal and some waste metal produces.
Samples were etched in Keller reagent solution in obtaining grain boundaries of the specimens as suggested in ASTM E-407 [14].
The grain boundaries clearly show between Al and Sn.
Micro void Grain Micro void Sn void Al 100μm 100μm b a.
Al void Sn Grain Sn Sn void Micro void 100μm 100μm Al Al void Figure 4: Microstructure of (a) Al-6vol%Sn (b) cross section Al-6vol%Sn (c) Al-6vol%Sn (d) cross section Al-20vol%Sn at 100× magnification Conclusion Composites Al-Sn had been done using direct conversion method by cold forging process in this study.

The average grain size is about 2µm and some macropores can be observed obviously.
The average grain size is about 1µm and no sintering phenomenon due to the low density.
The average grain size changes slightly, however sintering phenomenon occurred.
The electron thermal conductivity κe is estimated by the Wiedemann-Franz relation κe=σLT (L is the Lorenz number) [9].
The main reason is that CIP facilitates to sinter to accelerate the formation of grain; furthermore it is beneficial for the densification of ceramics.

The air draft negative pressure is greater, airflow hindered degree increases, the flow speed slow down, the quantity of o2 cross the complex is decrease, the reaction c+o2=co2 is weak, the quantity of co increases, the utilization rate of heat energy is reduced. 2.2 The dynamics analysis of solid fuel combustion in sintering material process In sintering mixture the shape of solid fuel is grain and powder, the combustion rate of fuel grain in the sintering mixture decide the residence time of high temperature region and the region width.
In actual production, due to the existence of ash and the formation of low melting point compound, carbon grains combustion in material layer is mainly decided by the diffusion speed, means KR ≥KD. and , so the equation is simplified as (6) Where A, n is constant and index, C is the concentration of O2 in gaseous phase, D is diffusion coefficient, d is carbon diameter, Re is Reynold number.
The equation shows that reduced carbon grain size, improve the fuel distribution of material layer, the d decreases, and the V increases, the burning rate of fuels accelerates; In addition, increase the concentration of O2 in gas phase, V will increase, the fuel combustion. rate will speed up.

There has been an increased number of scrapped products (beltlines) due to delamination of thermoplastic foil from plastic substrate during the summer period.
The beltline is composed of polycarbonate substrate and covered by thermoplastic foil in a moulding grain machine.
The in moulding grain machine is used for sticking the TPO foil with plastic substrate.
Process decomposition: Fig. 3 Production line 1 – application of glue to TPO foil, 2 – in mould graining, 3 – edge wrapping On the base of decomposition, we have looked for Y factors that could have an impact on the delamination of TPO foil from plastic substrate.
In moulding grain machine: - TPO foil heating temperature, °C; - time to start edge wrapping process, s; - length of TPO foil for wrapping, mm.

Silicon is commonly added in the production of carbon blocks to increase the micro-porous characteristic, and its action mechanism was investigated in detail[4]; As well, alumina, especially coarse-grained alumina is often added in the refractories to increase the anti-molten iron attack.
Reference [5] reported that decreasing the grain size to attain a material densification can increase the micro-porous structure and thermal conductivity of carbon refractories.
So, it is considered that using micron-sized alumina to substitute coarse-grained alumina may improve the performances of carbon blocks.
In this work, using micron-sized alumina to substitute coarse-grained alumina in carbon blocks was taken into consideration and the effect of reactive-Al2O3 on the porous strcture and thermal conductivity of carbon blocks was studied.
A large number of ball-like substances at the end of the whiskers identified as cristobalite and slender whiskers identified as β-SiC whiskers were easily found in the matrix of sample A0.

This treatment results in the development of lamellar structure with {100}a<110> crystallographic texture and grains strongly elongated along rolling direction [5,6].
Microstructure of medium-carbon steel after tempforming at 600°C with a rolling reduction of 75% (a) elongated grains in EBSD map, (b) lamellar structure with boundary M23C6 carbides.
Acknowledgements This research was funded by the Ministry of Science and Higher Education of the Russian Federation, grant number 075-15-2021-572.
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Inoue, Influence of Carbon Content on Toughening in Ultrafine Elongated Grain Structure Steels, ISIJ Int., 55 (2015) 1135-1144