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Experiment results and analysis The microstructure observation and analysis of 1Cr18Ni9Ti and 2Cr13 welding joint OM microstructure observation and analysis of 1Cr18Ni9Ti and 2Cr13 welding joint Fig.1 The structure of 1Cr18Ni9Ti and 2Cr13welding joint(OM) From fig1, because of quick heat dissipation vertical to welded joint, grain growth is fast along this direction, slow along others direction, column crystal forms in welded joint[2].
At the same time, cooling is rapid and grain is fine in the fusion zone.
On the contrary, grain is gross under welding heat circulation effect in HAZ.
From fig3, samples number of capacitive reactance arcs from little to big is: 5#<4#< 3#<2#<1#，the less is value of capacitive reactance arcs, the less is the amplitude of relatively low-frequency, the weaker is corrosion resistance.
Table 4 The result of Tafel fit Sample number Zone of welding joint I (Amps/cm2) 1# Austenite base metal 2.58E-08 2# HAZ near to austenite 9.03E-08 3# Welded joint 2.92E-07 4# HAZ near to martensite 3.08E-06 5# Martensite base metal 8.70E-06 Conclusion (1)The 2 mm 1Cr18Ni9Ti austenite stainless steel and the 2mm 2Cr13 martensite stainless plate, by TIG, under certain craft(DCEP), welded joint structure is lath martensite + residual austenite + carbide.

We all know that the process of constructing a decision tree will end up with more branch nodes when detailed classifications at higher levels are finely grained.
These two are the restricted number on the clear area value.
Variable precision rough set algorithm for constructing decision tree Weight limit the number of clear zone (LVPER) In the process of calculating the number of attributes in specific areas, the more number of attributes make the value of clear value bigger.
The trend of increasing number of specific areas with larger number of attribute values is under control.
The maximum number of steps is with the time complexity.

Previously, a number of technologies for cryptocrystalline graphite enrichment had been developed by the authors.
Previously, a number of technologies for cryptocrystalline graphite enrichment had been developed by the authors.
Materials and Methods The graphite of the Noginsk deposit is a fine-grained, uniformly granular material, the individual particles of which can reach 0,15 mm, the predominant particle size is less than 0,05 mm.
The distribution of the latter in the ore is uneven (from 5 to 45%) and is represented by impregnation (particle size from 0.05 to 0.001 mm), individual grains or aggregate formations that cut the ore in all directions.
Golovin, Report on the Research Paper "Develop, Manufacture and Conduct Commissioning Works of the Installation of Graphite Grains Layered Activation, Krasnoyarsk, 1997

Fig1. was shown number of cycles with the crack-length in the surface of various samples.
Thermal fatigue tested results of samples It was seen that annealed ferrite ductile iron was more excellent to resist thermal fatigue [4,5] than the others, and that its thermal cycles was nearly up to 500 times while the crack-length was only 4mm long; On the contrary, the capacity of the alloyed pearlitic ductile iron was the worst to resist to form cracks in sample surface, and its number of cycles was 25 times as its crack-length added up 8mm long, just as shows in Fig.1.
The crack of the grain boundary in the sample would decreased thermal fatigue resistance of bainite ductile iron greatly, just as shown in Fig2, for the crack was propagated in the sample.
During thermal cycles, many micro-cracks was initiated and expended between spherical graphite and grain boundary These micro-cracks connected each other and formed longer cracks, which made samples disabled.
Thermal fatigue resistance of ferrite ductile iron is best to the others in the paper; In the microstructure of samples in the article, a second phase, for example graphite, inclusion, coarse grain, would makes for cracks generated and decreased thermal fatigue resistance.

Therefore, in the year of the 20th century, production and application of lightweight aggregate concrete technology developed rapidly, mainly to the light-weight, high-strength development, extensive applications are retaining structure of high-rise, long-span structures and, in particular a large number, used in the production of small hollow block wall.
Since1950s China started to develop lightweight aggregate and lightweight aggregate concrete, mainly used in industrial and civil buildings large and small hollow block wall plate, a small number of senior and bridge construction of load-bearing structures and thermal structure [3].
Since the light aggregate concrete’s aggregates are kind of porous materials and several types of them are fly ash pottery grain, page rock pottery grain, and clay pottery grain(Fig.01).

Very high plastic zones observation: Half number of the cut parts were heated at 670˚C for 3h in an electric furnace.
The other half number were heated at 750˚C for 24h in the electric furnace.
The surface was etched to observe the recrystallized grains.
Due to the very fine recrystallized grain, it was impossible to observe macroscopically the recrystallized zone.
The very fine recrystallized grains are formed about 0.1mm from the outer surface(Fig. 4(c)).

Fig. 5 Two materials joined by Flowdrill method Fig. 6 Cross-section detail of sample In the Fig. 7 is shown the microstructure of the tested Al sample, where are seen the grain differences between the deformation of the grains in the collar and basic material.
The join of two plates are shown in the Fig. 8, where they have a very similar structure originated due to material mixing at higher temperature, only in very join area there is visible the decreasing the grain size.
Fig. 7 Deformation of grains of collar Fig. 8 Detail of material mixing Fig. 9 SEM of join boundary Fig. 10 Composition of filling phase in join area Summary Based on the experimental works, we made the conclusion that Flowdrill method as thermal drilling method has following advantages [1-3,5,7]: § It reduces the number of technological operations.
§ It reduces the number of necessary equipment for manual or automated production

Introduction The ordered B2 intermetallic compound NiAl possesses a number of promising properties which make it an attractive replacement material for superalloys.
The values of 1, 3, 5 are considered to represent the process of grain boundary diffusion controlled creep (Coble creep)[4], viscous glide of mobile dislocation (Class Ⅰ) and dislocation climb controlled creep due to lattice self-diffusion (ClassⅡ)[5].
The values of stress exponent for the creep deformation of binary NiAl reported by a number of authors scatter between 1 and 10.2[6].
Conversely, when tertiary creep is associated with microstructure changes, such as grain growth or overaging, large ratios tf/ tt have been obtained.
The failure mode exhibits the mixture feature of ductile-dimple in the grain cell region and intergranular fracture.

Results and Discussion Different holding time can affect the grain size of crystal of refractory materials .Chen’s [8] research show that holding time (i.e. the holding time of the process of ceramic agglutination) is the main stage of being compact.
If the holding time is too long, the crystal grain grows up rapidly through the recrystallization; if the holding time is too short, the crystal grain cannot grow fully.
Obviously, the crystal grain of samples which is 3h holding time were grow more fully, distributed more uniform, intergranular contact more closed, it has formed compact microscope.
Fig. 5 is the SEM images of the different number of times of thermal shock.
a b A Fig. 3 SEM images of the sample of hydration for 5h (a) surface (b) fractured surface Fig. 4 EDS of the rod-like e f c d a b Fig. 5 SEM images of the different number of times of thermal shock (a) 5 times, surface (b) 5 times, fractured surface (c)10 times, surface (d) 10 times, fractured surface (e)15 times, surface (f) 15 times, fractured surface Conclusions (1) The main crystalline phase of the light heat-insulation refractory materials is CAS2. (2)After the sample hydrated for 5h, the dissociated CaO react with H2O, then Ca(OH)2 react with CO2 product CaCO3 on the surface; but the hydrated phenomenon is not occurred in the intra of the sample .The sample has excellent anti-hydrated property. (3)After 5 times,10 times,15 times thermal shock cycle between 500℃ and 100℃, the surface and fractured surface are both not observed crack, it indicates that it has excellent thermal shock resistance property.

The correction is made as follows: (9) where: i – iteration number, Ti – temperature in ith iteration.
This effect is also observed for the grain size.
New grains measuring about 55 µm are created.
Grain size after the SRX after the second pass is shown in Figure 6a.
Grain refinement to 25-35 µm was predicted.