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Al couple, the reaction product penetrated into grain boundaries visible in the U-7Mo-6Zr alloy as shown in Figure 2(b).
Some grains are shown to be consumed by the reaction product.
The first method was to calculate the total number of pixels within the IL and divide it by the length of the IL giving an average integrated thickness.
The presence of the a phase allows for faster diffusion and typically nucleation of a-U occurs at grain boundaries [12].
TTT diagrams show U-10Nb-4Zr starting to transform after 10 hours, which agrees with the micrographs collected showing IL penetrating into grain boundaries and enveloping grains [16].

Requirements for microgeometry are mainly focused on the roughness parameters Ra [mm] (roughness), Pc [cm-1] (number of peaks) or Wa [mm] (undulation roughness).
It goes from roughening the surface of the work rolls by mechanical blasting of fine-grained granules (SBT - Shot Blast Texturing) to roughening work rolls by sparking (EDT - Electric Discharge Texturing), laser beam (LBT - Laser Beam Texturing), electron beam (EBT - Electron Beam Texturing) and electrolytic chromium (PRETEX - Preussag Texturing) [2, 3].
As it results from Fig. 8, the higher Ra of the work roll surface, the lower number of peaks on the rolls at the equal removal of the rolling mill.
As for Pc parameter, customers specified only lower tolerance value of number of peaks (Table 1, Ra 1.5 mm – Pc 158 cm-1).
Fig. 8 Dependence of number of peaks on arithmetic mean roughness of work rolls.

The effect of the heat treatment temperature on the Gd2Zr2O7 nanocrystal grain size was also analyzed.
At present, the synthesis of Gd2Zr2O7 nanopowders can be achieved using a number of soft chemical routes, including chemical coprecipitation [5-7] and hydrothermal and sol-gel methods.
The effect of the heat treatment temperature on the Gd2Zr2O7 nanocrystal grain size is discussed in detail.
The average grain sizes were estimated by the Scherer equation from X-ray diffraction patterns (see Table 1).
Fig. 2 XRD patterns of the Gd2Zr2O7 precursor annealed at different temperature for 2 h Fig. 3 Fourier transforms infrared spectra of (a) the Gd2Zr2O7 precursor and (b) the precursor annealed for 2 h at 900 °C Table.1 Grain size of Gd2Zr2O7 obtained from the precursors annealed at different temperatures for 2h Temperature/°C 600 700 800 900 1000 Grain size/nm 25.9 40.1 45.6 57.3 62.1 The Fourier transform infrared spectra of Gd2Zr2O7 precursor are shown in Fig. 3a.

The XRD analysis results showed that diffraction peak of Pd(111), Pd(200), Au(111) and Au(200) became sharp gradually with the extension of reaction time, crystalline phase composition and grain size of catalyst became bigger gradually.
Pd and Au was determined to the mainly active group of catalyst through a large number of experimental comparison.
This indicated that crystalline phase composition and grain size of catalyst became bigger gradually after reaction, it may be the primarily reason for affect the catalytic activity.
The XRD analysis results showed that diffraction peak of Pd(111), Pd(200), Au(111) and Au(200) became sharp gradually with the extension of reaction time, crystalline phase composi- tion and grain size of catalyst became bigger gradually.

The carbonation conversions for CMA and dolomite with the number of cycles were experimentally investigated.
During sintering, necks develop between adjacent grains and continue to grow, and the distance between grain centers is diminished.
Even, the conversion for CMA at 1100 ℃ is much greater than that for dolomite at 920 ℃ with the number of cycles, as can be seen in this figure.
Sintering is responsible to the decrease in the surface area and pore volume for CO2 sorbents with the number of cycles.
CMA maintains much greater carbonation conversion than that for dolomite and limestone with the number of cycles at the carbonation temperature of 650-700 ℃.

According to Sato et al.[1], the statically recrystallized grain size in the nugget region is determined predominantly by the peak temperature in the weld: the higher the peak temperature, the larger the grain size.
Some effect of welding speed may also be involved, but as the grain size (for static grain growth) is exponential with temperature and linear with time, the peak temperature will exert the dominant influence.
Grain sizes on the order of 10's of micrometers and less than 1 μm have been reported.
Depending on the nugget grain size, there may be some increment of strengthening due to microstructural refinement.
Reynolds, Science and Technology of Welding & Joining, Volume 10, Number 6, December 2005, pp. 725-736(12) 10.

Tree grain brocade emerged in the Northern Dynasties chose a piece of leaf as life tree, and this theme could also be seen in Chinese tradition, while there was ribbon on the petiole of the leaf grain, which reflected the western influence[3].
Life tree grain always appeared as symmetric form in Persian art, which can be apparently showed in tree grain brocade.
Among them the images of elephant, lion, cattle on grid beast grain brocade were influenced by Buddhism.
In beast grain brocades of Six Dynasties, elephant images were realistic, while horse, deer images were very different from Chinese traditional grain, where the horse can fly.
Geometry skeleton included tortoise skeleton, check with flower in it skeleton, chess grain skeleton, etc.

Among these processes, equal channel angular pressing (ECAP) is one of the preferred techniques for grain refinement.
For a number of engineering applications, mechanical and structural proprieties i.e. microstructure homogeneity and hardness are very important.
Langdon, Principles of equal-channel angular pressing as a processing tool for grain refinement, Prog.
Langdon, The evolution of homogeneity and grain refinement during equal-channel angular pressing: A model for grain refinement in ECAP, Mater.
Langdon, Principle of equal-channel angular pressing for the processing of ultra-fine grained materials, Scr.

The numbers of experiments were determined based on the Taguchi method.
The grain size is smaller than the parent mild steel when compared, according to the comparison.
One of the key elements affecting the hardness test is the grain size.
Additionally, as compared to the parent mild steel and weld-machined samples, this weld-forged specimen had the smallest grain size.
From microstructure analysis observation, the welded specimen has an irregular grain structure compared with the parent mild steel specimens because of the grain formation at an irregular temperature during the layer-by-layer welding. 4.

However, higher magnesium content in the alloy makes it natural aging kinetics faster due to large number of quench in vacancies after solution treatment.
Figure 2: Optical microstructure of as extruded rod of 85 mm dia.V65 alloy along the rolling direction The microstructure also shows segregation free grains with clearly visible grain boundaries.
After caliber rolling at different temperatures, significant grain refinement has taken place due to very large acuumulated strain leading to formation of fine grained microstructure.
However, in the as rolled condition, the grain boundaries can be delinated with little clarity.
Further, in specimens rolled at higher temperatures, microbands within the grains can be seen.