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The microstructure analysis showed that the low strengths of T6 A356 alloy should be at least attributed to the absence of the magnesium-based intermetallic phase, coarse grain structure and the presence of porosity, which resulted from the HPDC process, MIG welding and thermal treatment.
Therefore, the high vacuum (V-HPDC) process, advances the die casting process and makes it more competitive for mass production of structural automotive components with enhanced properties and significantly reduced number of defects [2-5].
Based on the optical microstructural analyses, the grain size and silicon particle in the fusion zone (ER4043) were finer than those base metal, which resulted in an increase in strengths of the fusion zone of the filler alloy ER 4043.

The study of the behaviour of the two previously mentioned parameters has been done by means of the technique of design of experiments (DOE), which allows us to carry out the previous analysis performing a relatively small number of experiments.
In this case, a 2 5-1 fractional factorial design, whose resolution is V, has been selected due to the number of factors considered in the study.
In this work, a reaction-bonded or siliconised silicon carbide (SiSiC) has been selected due to its large number of applications: heat exchangers, parts subjected to high wear, high temperature gas turbines, bearings, seals, lining of industrial furnaces, being among the most important ones.
The resulting microstructure has a low porosity and a very fine grain, providing a density of 3,1 g/cm3.
There are a large number of factors to consider within the die-sinking EDM process but, above all, there are five that could be underlined: the intensity level of the EDM machine generator (I), pulse time (ti), duty cycle (η), open-circuit voltage (U) and the flushing pressure of the dielectric fluid (P).

Test samples of RCA have always different source, grain composition and other physical and mechanical properties, which are variously described in each different paper.
Type of MSC is closely related to amount of fine particles, water absorption and shape index of grains.
The smaller number of gained points for crucial factors is, the more suitable RCA is.

Thus a composite of silicon carbide with ductile and highly conductive copper seems to be a promising new material for a number of applications.
All MMC show a heterogeneous microstructure with SiC grains up to 20 µm (Fig 4).
Because the SiO2-layers surround the SiC grains completely, the ceramic backbone of the composites merely consists of SiO2.

Powder grain size distribution was obtained using an Occhio Alpaga 500 Nano® granulometer.
- Tests involved 10,000 and 100,000 cycles, i.e. the number of impacts
Crater diameter and depth depended on testing parameters such as impact angle, impact number and temperature (Fig. 4).
The outer zone (numbered 0 in Fig. 14), which corresponded to the early stage of wear, showed that most of the coating remained sound.
In zone number 1, surface could transform due to plastic deformation, which initiated TTS formation.

The results of chemical compatibility measurement show that a small number of Gd and/or Ce ions may melt into the lattice of BSCN0.2 to form BSCN0.2-GDC solid solution.
The adjacent GDC grains likely affected the microstructure of BSCN0.2 material and restrained the thermal expansion behavior of BSCN0.2 grains.

There is a central island between the two tunnel junctions, its three electrodes are source electrode, drain electrode and grid electrode which used to control electron number of quantum dot.
depends on transmission coefficient of barrier to electron wave and the number of independent electron wave modes.
For current to flow the number of electrons on the droplet must fluctuate between N and N+1.
Its basic structural scheme is shown in Fig. 5, the nanometer crystal grain (quantum dot) is placed in oxidizing layer which is between channel of MOSFET structure and control gate.
When eliminate the dependence on variable, the equation is simplified as: (2) N is the number of electrons in quantum dot, is the total capacitance of quantum dot.

The specific testing process as follows: (1)The nitrogen flow rate were:9,12,15,18,21,24,27sccm,sputtering temperature130℃, sputtering time 15min; (2)The sputtering time were: 5,10,15,20,25,30min, nitrogen flow rate 18sccm, sputtering temperature 130℃; (3)The sputtering temperature were: 50,60,70,80,90,100,110,120,130,140,150,160,170,180, 190,200℃,nitrogen flow rate 18sccm, sputtering time 15min; 2 Test and analysis 2.1 The influence of nitrogen flow rate to the ZrN film corrosion resistance The nitrogen flow rate of this experiment process were: 9,12,15,18,21,24,27sccm,sputtering temperature 130℃,sputtering time 15min,all the sample number was 1-7.After the experiment, 1-7 sample do the corrosion resistance test which use YWX/Q-250 type salt spray device in accordance with the national standard GB/T10125-1997.
structure and form more pore space, which made corrosion resistance reduce. 2.2 The influence of sputtering time to the ZrN film corrosion resistance The sputtering time of this experiment process were:5,10,15,20,25,30min,sputtering temperature 130℃, nitrogen flow rate 18sccm,all the sample number was 1-6.
Tab.2 The influence of sputtering time to the ZrN film corrosion resistance sample number 1 2 3 4 5 6 sputtering time(min) 5 10 15 20 25 30 film thichkness(nm) 30 45 70 85 110 135 corrosion grade GB/T10125-1997 7 8 9 8 8 7 Fig 2 The relationship between sputtering time, film thin and corrosion 2.3 The influence of sputtering temperature to the ZrN film corrosion resistance The sputtering temperature of this experiment process were:50,60,70,80,90, 100,110,120,130,140,150,160,170,180,190,200℃,sputtering time 15 min,nitrogen flow rate 18sccm,all the sample number was 1-16.After the experiment,1-16 sample do the corrosion resistance test which use YWX/Q-250 type salt spray device in accordance with the national standard GB/T10125-1997,the results as shown in figure 3.
When the sputtering temperature was low,the Zr ions and N ions energy was small,which can not fully diffused.This result in Zr ions and N ions connection probability was low and sputtering a small number of ZrN compounds on the aluminum surface,therefore appear more holes and defects.With the increase of temperature,Zr ions and N ions gained enough energy,more and more ZrN compounds was deposited on the aluminum alloy surface,which increase the corrosion resistance[9,10].When the temperature was more than 150℃,the high temperature will increase the thermal stress,lead to grain become big in the film structure,and reduce the corrosion resistance. 3 Conclusion (1)The ZrN film corrosion resisitance increased with the nitrogen flow rate increase,when the nitrogen flow rate reach 18sccm, the ZrN film corrosion resistance reach the best.With the nitrogen flow rate increase,more and more nitrogen molecule connect with sputtering ion which form an compact and almost without any pore space ZrN
(3)With the increase of sputtering temperature,the ZrN film corrosion resistance was increased gradually.When the temperature reach 130℃,the corrosion resisitance reach the best.When the sputtering temperature was low,the Zr ions and N ions energy was small,Zr ions and N ions connection probability was low and sputtering ZrN compounds number was small,which reduce the film corrosion resistanceWith the temperature increase,more and more ZrN compounds was deposited on the aluminum alloy surface,which increase the corrosion resistance.

The relationship between the number of the grinding passes and the radial blade wear is shown in Fig.5.
The relationship between the number of grinding passes and the radial blade wear is shown in Fig.6.
Figure 8 shows the relationship between the number of the grinding passes and the radial wear of the CBN blade.
(3) The radial wear of the blades with WA, diamond and CBN grains drastically are decreased to 2/3 ~ 1/3 when the small gap nozzle is applied to the slit grinding with various materials.
Fig.8 Relationship between number of grinding passes and radial wear of CBN600M blade in slit grinding of SUS630 Radial wear of CBN blade Hm � �Conventional nozzle (Q=8 l/min) � �Small gap nozzle (Q=0.7 l/min) 600 1200 1800 2400 3000 10 20 30 40 50 Grinding length mm 100 50 150 200 Vs=52m/s, Vw=3.5mm/min, a=3mm/pass, Down-cut CBN600M( � 100xt0.17mm), SUS630( L=60mm) 0 0 Grinding passes 0

It is layuped in the sequential pattern along the grain, then mitered, lapped or butted at the end, gelatinized and hot-pressing processing.
At the other end of the plank, the ultrasonic signal transmitted to the MCU via receiving circuit triggers the Single Chip Microcomputer external interrupt which makes the count stop so that the current number T1 can be available from TCNT1.
At first, pulse number N = 0, the number of rotations M = 0, each turn rotary encoder sends 500 pulses, and the arrival of each rising edge triggers the external interrupt INT0, N + +.
At the other end of the plank, the ultrasonic signal transmitted to the MCU via receiving circuit triggers the Single Chip Microcomputer external interrupt which makes the count stop so that the current number T1 can be available from TCNT1.
Materials Evaluation,1996(54):51425171 Table 1 Table Type Styles SUMMARY ANOVA groups Observed number summation average variance of the number Column 1a 8 29331.41 3666.427 7339.683 Column 2 8 29692.8 3711.601 6481.811 Analysis of variance Different sources SS df MS F P-value F crit between Groups 1 29331.41 8162.69 1.181159 0.295478 8.861593 Within Group 14 29692.8 6910.747 Total 15 Fig.6 Time and Length Measurement Subroutine