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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.

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.

From bonded specimens by 200 rpm condition, there was many grain existed the part of deformed graphite on SZ zone.
Fig.6 shows relation between distance from bonded center and Vickers hardness number by preheat 573 and 773K conditions.
Vickers hardness number was low relatively.
Fig.6 Relation between distance from center (4.25mm from surface) and Vickers hardness number by preheat 573K and 773K conditions.

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.

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.

Fig. 2 Elements of ultrasonic machine (AP-1000) [4] Basic components of ultrasonic machine tool Ultrasonic machine comprises of number of essential elements which are necessary to make the working of machine proper.
Predicted results was shows that MRR will gradually increase, with the increase in size of the abrasive particles for miller’s model and for Shaw’s model, MRR is more in grain hammering model than that in grain throwing model.
The abrasive recommended for the ultrasonic machining of nitride ceramics are boron carbide with grain size of 60-100 µm and silicon carbide with grain size of 80-100 µm.
Oversize also depends upon brittle fracture characteristics and the grain structure of the work material.
The results showed that the diamond grains were dislodged from the tool due to bond fracture.