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In the text, SSVs of an orientation x are numbered x1, ..., x4, i.e. the basic variant and three other ones, generated respectively by two-fold axes 2NDL , 2TDL , 2RDL .
Journal Title and Volume Number (to be inserted by the publisher) 3 4 Title of Publication (to be inserted by the publisher) Figure 2b shows a much less typical case of nucleation in a band with the orientation close to the Cube component.
In the foils prepared from ~10%recrystallized material two types of new grains were observed: small, isolated grains and much larger grains formed complex sets of recrystallization twins.
The orientations of small grains - with the area at least 102 times smaller than the area of the largest grain observed - are distributed around the deformation texture components.
Small, isolated grains could be found in the neighborhood of complex recrystallization twin sets. 6 Title of Publication (to be inserted by the publisher) Differences in the size of new grains can be related to the characteristics of orientation relationships between a new grain and the deformed matrix; quite different for small and large grains.

With the transformation of co-doped inhibitors’ content, the grain growth is inhibited and the grain size achieves 490 nm at 0.4% Cr3C2 / 0.3% NbC.
With its exceptional hardness, wear resistance and high mechanical strength, it is becoming very desirable for a number of applications.
Until now, the most successful way of controlling the WC grain growth is the addition of small amounts of WC grain growth inhibitors.
(a) (b) Fig. 1 SEM graphs of cemented carbides: (a) 0.4%Cr3C2+0.3%NbC; (b) without inhibitor As shown in Fig. 1, larger numbers of dark zones which may represent pores can be observed in (a) than (b), and the phenomenon will be studied in the next work.
Secondly, the presence of inhibitor NbC / Cr3C2 at the WC–Co interface prevents the transfer of the phase and stops the WC grains connected and growing, which results in the increased amount of the single WC grain, ensuring the inhibition of both normal grain growth and abnormal grain growth of the WC grains [14-19].

The Aero-thermodynamic Effect Simulation Study of Solid Motor Grain Wen-geng PAN1,a, Tao LI 1,b, Guang-rong BIAN1 and Jin-rong CAO1 1Department of Aviation Ammunition, Air Force Logistics College, Jiangsu Xuzhou 221000, China anjlgdx2007@sina.com, bjiangnanlt@sina.com Keywords: missile, solid motor grain, aerodynamic heating, temperature field.
For high-speed flight's missile, thermal coefficient of expansion between the different structural and element will be different simultaneously, when the aerodynamic heating will produce, the grain and the thermal insulation layer will also be appeared the crack phenomenon in the influence of expand with heat and contract with cold rules.
Visible, it is not that the lesser number of the crack on the propellant column the smaller influence for the solid rocket motor, as long as the main crack and auxiliary crack arranged in a certain way, it is possible to reduce the harm of the crack to the propellant column.
Research of The Solid Propellant Grain Structural Integrity under Temperature and Pressure Loads.
HongDu Science And Technology, 2005 (1) [3] Wei Zhongwei, Xiao Jun, Liu Jianjie, Thermal Stress Failure on Heat Insulation Coatings for Airborne Missile Fuselage Connection, Aero Weaponry, 2006 (4) 50-52,59 [4] Liu Zhuqing, Yan Shidong, Ding Biao, Effect of Grain Crack to Solid Rocket Motor Performance, Journal of naval aeronautical engineering institute, 2007 (4) : 443 -444.

A number of studies have been carried out on the use of Holographic optics [4-6], with success demonstrated of the technique in terms of beam control for cutting.
A number of welds ~30 mm length were completed before the sheet was removed.
The grains in this deposit are more equiaxed than in Fig.3(a) with a smaller grain size seen on the side with the lower energy input.
There is clearly a grain refinement with the low energy ORP-HOE with a larger 200µm 200µm grain size seen in the high energy ORP-HOE.
The grain size within the weld bead/deposit can be controlled such that a finer more equiaxed grain structure can be developed.

The presence of grain boundary particles leads to enhanced grain stability at elevated temperatures.
Therefore, the deformation temperature is kept as low as possible to minimise grain growth.
All alloys show enhanced grain stability during heat treatments due to the presence of the grain boundary particles.
The fatigue limit is reduced by 10% due to weakening of the grain boundaries.
The work on Ti-6-4 alloy has been supported by the Arbeitsgemeinschaft industrieller Forschungsvereinigungen (AiF), Project Number IGF 253 ZN.

Severe plastic deformation by continuous ECAE process affect the microstructure in some extent depending on the number of passes as shown in Fig. 2(b)-(e).
This microstructure also has the sub-grains separated to each other by low-angle grain boundaries (LAGBs) as indicated by double arrows in Fig.
As the number of passes increased, the dislocation density increased and smaller sub-grains form with mostly LAGBs.
After processing, the strength of steel increased continuously with an increase in the number of passes.
However, with increasing number of passes, the texture component from 4th pass onwards remains same i.e. {110}q components.

The average grain size of the composites decreased from 110.35μm to 52.07μm when the TiB2 particles is 4.47%, and the grain size changed slightly when TiB2 content increased further.
Grain size and hardness of the as-aged composites Number 1# 2# 3# 4# Grain size (μm) 110.35 52.07 51.41 51.94 Hardness (HB) 189 197 202 206 Fig. 1a to 1d showed the microstructure of the casting composite with different TiB2 content.
The grain size of the four composites with different TiB2 content are shown in the Fig. 1e black line which correspond with the Grain size in Table 2.
The average grain size of the composites decreased from 110.35μm to 52.07μm when the TiB2 particles is 4.47%, and the grain size changed slightly when TiB2 content increased further.
Because of the difference of thermal expansion coefficient of TiB2 particles and matrix, a large number of additional dislocations were produced around the TiB2 particles, which resulted in hardness increased greatly.

(The average width of the α-SiAlON grains is the mean of the minimum distance passing the geometric center of each grain).
Since the backscattered electron intensity depends mainly on the mean atomic number, the differences in the amounts of neodymium presented in the α, β SiAlON and grain boundary phases make them easily identified.
Grain growth during post heat treatments.
A grain growth was observed in α-SiAlON grains related to high temperature heat treatment and holding time.
Additionally, results of measurement of grain size according to LSW theory showed that grain growth mechanisms are different for width and length of grains.

Typical fluorescence spectrum of alumina phase. 5975 6000 6025 6050 6075 6100 6125 6150 6175 Wave number　(cm -1) Intensity (a.u.)Results and discussion Figure 3 shows the SEM images of ZTA with various zirconia contents.
The black and white grains correspond to alumina and zirconia grains, respectively.
The Raman study showed that peak position of Cr 3+ fluorescence spectrum shifted toward lower wave number with increasing zirconia content, namely with increasing monoclinic fraction.
The peak shift toward lower wave number means increase in tensile residual stress stored in alumina matrix (Fig 6).
Black and white grains indicate alumina and zirconia grains, respectively.

The improving effect of rubber powder is better than rubber grain.
The biggest grain size of rubber powder is 0.28mm and the biggest grain size of rubber particle is 3~4 mm in diameter.
Fig. 1 indicates that c Relative dynamic elasticity modulus P appears to gradually decrease with increasing freezing and thawing cycle number.
The maximum freezing and thawing cycle number reaches 150.
But too much rubber content results in decreasing frost resistance and can make relative dynamic elasticity modulus rapid decline with number of freezing and thawing cycles