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After blasting, by scanning the sample three times, crystal grains can be recognized, indicating that the modified layer has been removed.
Figure 6 shows the thickness of the wafer removed as a function of number of scans.
After two scans with increasing the number of scans, the removal rate reduced, because the material layer being removed changes from the modified layer to crystalline silicon.
Fig. 6 Thickess removed as a function of number of scans Thickness removed µm Scanning times 25µm (a) Before blasting (b) After blasting (c) Wire sliced Fig. 5 SEM images of silicon wafers, (a) before blasting, (b) after blasting and (c) wire sliced Summary We have demonstrated the modified layer induced by W-EDM by abrasive blasting.

Establish the Network We can specify input level nodal point number to be 3 by the input matrix, According to the rule of Kolmogorov, we may determine that the concealment level nodal point number is 5; The output level nodal point number is 1, then we get the BP neural network model.
Examples show that Levenberg Marquardt. algorithm Based on the improved algorithm of BP neural network training results from the accuracy and convergence are superior to the traditonal BP neural network, it shows the method using to predict the grain yield is completely feasible, improve the prediction precision and accelerate the convergence speed.

After component be subjected to stress circulates of certain number of times under circulation load, first some part of crystalline grain appear some short and thin glide lines, and show sequent disturbed glide pedestal sits, and produce the stress concentration due to forming the gap or blow-up on the surface.
As the number of times of circulation increases, new glide lines arise again on the old glide lines, and wider glide bands formation gradually.
Further increase the number of times of stress circulation; size and quantity of glide bands obviously increase.

Introduction Exchangeability of components for energy and heating boilers depends on the specific technical design, construction and arrangement of a number of other factors.
These samples are valuable not only because of the number of operating hours (2.5x105 hrs), but also that reports about the results of measurements of mechanical properties of the samples taken in the manufacture of drums were available.
There is also the exact number of operating hours, which is 250 200 (boiler K4) and 247 319 hours (boiler K5), respectively.
Microstructure of both as-exposed drums is formed by ferrite grains with significant carbide precipitation, mixture of lamellar and globular pearlite, and probably globularised fraction of upper bainite (see Fig. 2).

Introduction Attention of number of research institution is currently focused on the reducing of CO2 emission.
Measurements were realized in the age of 7 days because binding system formation during maturation affects number of final properties.
Just about 70% of grains is smaller than 0.125 mm.
Ceramic powder is a cement supplementary material which can find number of practical application.

Applying a hardened layer certain thickness on the detail's surfaces or directly applying it to the required depth in the working part can be a method of increasing the value a number mechanical characteristic of materials [4,5].
Table 1 – Results of measurement of microhardness [HV] Measurement number Sample 1 Sample 2 1 265.3 215.7 2 261.6 198.9 3 245.6 259.7 4 243.9 254.0 5 243.9 220.6 6 238.5 267.6 7 220.4 261.6 8 225.1 222.2 9 244.5 223.3 10 245.6 204.8 Mean value 241,2 232,8 Discussion It is possible to draw conclusions based on the results of studies on the preparation, investigation of microstructure and mechanical properties, experimental materials strengthened by WC and TiC dispersive particles in various ways: Investigations microhardness sample No. 1 showed that a properties gradient is observed from the outer (working) part of the sample to the other side: on the outside, the microhardness is 265.3 HV and gradually decreases to 245.6 HV.
Along with the possibility of obtaining a gradient of properties castings, the proposed method of hardening parts has a number of advantages over existing methods (disperse hardening, dispersion hardening, laser surfacing): 1) relative cheapness and simplicity; 2) location of the particles in the desired area (working part) of the casting; 3) possibility of using the method in almost any industrial production of cast parts.
Jones: Grain boundaries: Their Character, Characterisation and Influence on Properties (Institute of Materials.

The size and layout of the dimples depends on the grain size.
The generation of fracture surface is accompanied by significant plastic deformation associated with increasing the number of active slip systems at a higher strain rate.
On the fracture surface, the number of secondary cracks and voids that are generated in direction of lines has increased.
- With the increasing strain rate, plastic deformation becomes less significant and there is greater number of voids that are oriented in the direction of lines, dimples are shallower.

The metallographic photo of the alloy on the rolling plane is shown in Figure 1, which indicates that size of the grains is about 10 μm.
It is obvious that the number of dimples in Figure 4(d) are more than that in Figure 4(b), which indicates that the number of dimples increase when rising temperature.
Acknowledgement This work is supported by the National Natural Science Foundation of China under grant number 11872359.

A phenomenological model of domain wall motion is used in computation, and the effects of ac electric field amplitude and frequency, number of layers, and property gradation on the deflection of the cantilever actuators are examined.
Setting β =0 and ∆l = ∆l0 exp(iωt), from Eqs. (8)-(10), we have x1 l l ∆l E0 exp(iωt) Ps γsO x3 Domain wall Domain (a) (b) Fig. 1 Illustrations of (a) grains in piezoelectric ceramics and (b) basic unit of a crystallite with a displaceable domain wall.

A number of the data are collected through wide literature surveys and experiment, and evaluated by the C* parameter.
In this paper, to evaluate the CCGR of the type 316SS series: 316SS, 316FR and 316LN, a number of CCGR data were collected through wide literature surveys and experiment.
(1) Where εf* is the creep ductility and its value is determined with readuction of area, and rc is the size of the process zone and its value is determined with grain size of materials.