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The use of cemented carbide tools for cutting punch, cutting plate or bending elements lead to a higher piece number compared to traditional materials with significant lower abrasion resistance.
Numbers of control factors in present case are four.
Therefore, total number of runs = 24+2*4+7 = 31.
This is because with an increase in wheel RPM, as the number of abrasive-workpiece interactions per unit time increase, the number of spark discharge per unit grain increases.
At higher current, increase in maximum protrusion height of grains also leads to deterioration of surface finish.

The results show that in the structure of the stress concentration and cabinet material number ZL101 cast aluminum defects such as inclusions, porosity are the main cause of fatigue crack initiation and propagation.
By looking at high magnification metallographic (Fig.5) can be found that the material eutectic Si dot, it is relatively evenly distributed between α（Al）-phase, the grain is bulky and arranged in a tree, internal organization is loose.
Corresponding to the vehicle load spectra measured 2.22 km import AWP platform, calculated under the actual load spectrum cabinet dangerous parts of crack initiation life contours (Fig.9), The figure 11 shows the fatigue life of reliability for dangerous parts of 50% of the minimum value is 5889.4, so the corresponding vehicle distance L is: L＝5889.4×2.22 km＝13074.5 km （2） Conclusions The main reason of a tracked vehicle transmission casing fatigue fracture failure is: First, the manufacturing process of the transmission cabinet, due to the technological aspects of the problem, there is slag, porosity, loose, coarse grain thick tissue defects such as loose and cause localized stress reduction and effective cross-sectional area of focus; Second, due to the factors cabinet structure design, the screw hole center gear cabinet countershaft bearings beneath the right edge of the bearing hole distance too close, causing local stress concentration
Performance of the Thickness of the Aluminum Alloy Grain LY12 C2 [J].

Introduction Metal-nanoparticals ,their oxidation resistance is poor because of the surface effect.The object of studying nanomaterials＇passivation is to decrease the surface activity so that it can stay in the air longer, to obtain the ideal nanomaterials.It has been a number of ways on the reaserch of surface passivation of nano-materials,such as formed self-assembled protection layer or put organic film on the surface .However, pollution the surface of nanoparticles is the disadvantage , brought impurities in the application.
The Fe (110) peak is very sharp, indicated that the crystal grain was more complete, has no defects.
In this paper,we measure the crystal grain size of Fe nanoparticles by small angle XRD and XRD,and calculate the particle radius by the Jinie ear.
Besides,also measure the dislocation density, lattice parameter, root mean square strain, The results show as table 1: Table 1 The calculation of Fe nanoparticles Samples name particle radius [nm] lattice rameter a[nm] root mean square strain dislocation ensity [cm/cm2 ] No oxidated Fe nanoparticles 23.42 0.286 2.156×10-5 7.505×1011 oxidated Fe nanoparticles 23.59 0.287 4.207×10-４ 7.115×1011 The result indicates that the average crystal grain size of Fe nanoparticles after oxidized has increased slightly.
Fig.5 The curve of the changs of O in the nanoparticles Fe with time Conclusions (1) Study of metal nano-particles effective grain size between a dozen nm to 40 nm, particles with a complete form； (2) Oxide concentrated in particle surface.

Introduction It is now well-established that the most favorable places of microcrack nucleation are twin and grain boundaries [1].
Formation of the stable slip bands starts at early stage of deformation and is over after 10% of the total number of cycles is completed.
Dislocation clusters and slip bands Formation of big number of dislocation clusters in parallel slip planes is very usual during fatigue tests of the samples.
by this formula gives different values for different grades of steel and number of dislocations.
The microcrack propagation direction may change at the boundaries of grains, subgrains and twins.

It has also permitted the calculation of 'depth' concentration profiles of the diffusant such as tracer concentration depth profiles from the well-known thin-film or instantaneous tracer source condition for such problems as diffusion in the presence of grain boundaries, segregation of the diffusant to the grain boundary and within nanocrystalline material.
The regions Ω1 and Ω3 are mapped onto a fine grained square planar lattice of mesh size a.
The idea is simply to keep the number of virtual particles constant on this surface plane at, say, 10 5 for all diffusion times.
Over a period of time, as the material absorbs more diffusant, the number of particles in the system naturally increases.
Gust, in Fundamentals of Grain and Interphase Boundary Diffusion, (Wiley; Chichester) 1995

., TMR&D Innovation Centre, Lingkaran Teknokrat Timur, 63000 Cyberjaya, Selangor,Malaysia a rosidah@tmrnd.com.my Keywords: LTCC, glass-ceramic, sintering, grain size, microstructure Abstract.
This technology will allow a number of interfaces and the reduction of the overall substrate size [2-3].
During the formation of sintered bodies from the compacted layers, the grains are not preferentially oriented so that the density is not homogenous at this area (via hole).
When sintered at higher temperature, the grain size and the microcrack size were increased.

In polycrystalline materials, internal residual stresses raise during mechanical processing, due to the elastic-plastic behaviour of the grains.
Each grain is subjected to a local mechanical state: elastic strain (and stress) must be present in order to maintain the compatibility of total strain between neighbour grains [6].
A compact design involving a convenient number of experiments is needed.
The first step of designing an experiment with known number of factors in Taguchi's method is to select the most suitable O.A..
Observations achieved in a Scanning Electron Microscope indicated that the microstructure consists of acicular alpha (platelets) mixed to slightly equiaxed prior beta grains.

As the number of loading cycles is increased, damage grows.
After a certain number of cycles, a crack is developed and, at the end, the final failure of the shaft ocurrs.
In the case of the axle, the localized shear plane usually occurs at the surface or within grain boundaries.
This is of the order of a couple of grains on the maximum local shear stress plane.
In this case, n1 is the initial number of load cycles, which are applied at a higher stress level.

The results showed that in the optimal conditions, ultrasonic electroless plating can increase the coating hardness value by 170HV and extend the coating corrosion resistance time by 130s; inorder to reach the same corrosion resistance time or hardness value, the temperature under ultrasonic decreases 20℃ than that without ultrasonic wave; ultrasonic wave can improve the deposition rate, refine the grains and inhibit the nano particles to agglomerate.
The ultrasonic cavitations increase the number of activated ions and collision times of ions, which is helpful for the coating formation.
It will cause high temperature and pressure when the bubbles break up, which not only is favorable for crystal nucleation, but also increases the number of activated ions and collision times of ions.
The coating forms easier because of the ultrasonic cavitations which can transfer energy to the ions in the bath to speed the ions and increase the number of activated molecules and collision times of molecules, so the deposition rate increases.
In the optimal conditions, ultrasonic electroless plating can increase the coating hardness value by 170HV and extend the coating corrosion resistance time by 130s; in order to reach the same corrosion resistance time or hardness value, the temperature under ultrasonic decreases more than 20℃ than that without ultrasonic wave. 2 Through contrast of microscopic structure between the coating obtained by ultrasonic electroless plating and the coating obtained by electroless plating without ultrasonic wave, it can be concluded that ultrasonic wave can improve the deposition rate and refine the grains. 3 By observing the TEM image, all particles in the coating obtained by ultrasonic electroless plating Ni-P nano Al2O3 on AZ91D magnesium alloys achieve nanometer level.

Recent works showed that it is possible to decrease the lattice contribution to the thermal conductivity of materials by enhancing the scattering of the phonons at the grain boundaries in nanostructured materials [1].
Nanostructured bulk materials can be obtained by spark plasma sintering without significant grain growth resulting from reduced time and temperature needed for the densification.
Cold pressing would be also an interesting alternative for avoiding grain growth.
The total number of pulses used was 36,000 (approximately 60 min).
Mirror Lens Pump Nd:YAG Laser (532 nm, 10 Hz) Nozzle The electrical resistivity increases as the number of nano-particles introduced is enhanced for both n-and p-type materials, resulting from the enchanced number of interfaces.