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Therefore, cracks propagete from there to the center of the bonding area, grow along the boundary of fine and coarse grains and lead to the lifting off of aluminum wire.
Table 1 frequency Frequency and temperature swing of cycle test Number frequency(Hz) swing ΔT(oC) F1 5k 100 F2 5k 50 F3 5k 50 F4 1k 50 F5 1k 50 F6 1k 100 The Collector Emitter ON voltage, Collector Emitter ON current and case temperature were in-situ measured and preserved by data acquisition system until failure of the IGBT under test , which was observed as a large increase in Collector Emitter ON current caused by latch-up [3]. 4 Prognosis 4.1 data preprocessing In order to facilitate a more accurate prediction of RUL of IGBT, we need to compress and convert the raw data extracted to get the best features in a low-dimensional space.

（K >1） (2) Coefficient K determines the number of the adsorbed seeds.
Magnetic Attraction Test of the prototype Prototype experiment’s aim is to test whether this design can realize single-grain precision seeding.

Table 1 The collection of quality problem Serial number Problem Frequency percentage Accumulated percentage 1 fog painting and gloss loss 69 42.8% 42.8% 2 spray leakage 26 16.8% 59.6% 3 sagging 23 14.7% 74.3% 4 pinhole 15 9.5% 83.8% 5 bubble 10 5.9% 89.7% 6 Grain 6 2.8% 92.5% 7 Paint film thickness 5 2.5% 95.0% 8 others 9 5.0% 100.00% In total 163 100.0% 100.00% 2.

Even so, the dominating microstructure of either deposit was dendritic and consisted of columnar grains that span the entire length of the re-build (Figs. 1g-h).
Specifically, the relative density increased from 98.5% to 99.3% with increasing energy between 18 and 24 J·mm-1 and from about 98.1% to 99.3% with increasing number of re-melts from one to three (Fig. 2a).
These processing parameters were observed to also influence the average pore size; the pore diameter decreased from roughly 24 to 21 µm with increasing beam energy and from 23 to 19 µm with increasing number of re-melts (Fig. 2b).
Nonetheless, despite the decrease in the growth rate of the BNi-2 deposit with increasing number of re-melts, the beneficial effect of an increase in the relative density (from 98.1% to 99.3%) and a decrease in the pore size (by 5 µm) with increasing number of re-melts from one to three (Fig. 2a) may be required for high-end applications.
Deposits produced by EBFF on 321 SS. 97.5 98 98.5 99 99.5 Number of Beam Passes Relative Density, % 97.5 98 98.5 99 99.5 15 20 25 30 Beam Energy J·mm-1 1 2 3 (a) 20 J·mm -1 2 re-melts 17 19 21 23 25 Number of Beam Passes Pore Size, µµµµm 17 19 21 23 25 15 20 25 30 Beam Energy J·mm-1 1 2 3 (b) 2 re-melts 20 J·mm -1 Figure 2.

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

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.

An interesting feature of the silicon nitride-rich region in low atomic number Ln-Si-Al-O-N systems is the number of structurally different phases which occur close together with similar compositions.
0.70 0.14 - 80 20 α-sialon ~4 0.75 0.03-0.17 - 100 - β-sialon ~4 0.75 0.00 - 100 - N coordination by Si,Al Al substitution is expressed as number of Al atoms per formula unit
The last four columns show the percentage of nitrogen atoms coordinated by different numbers of (Si,Al) atoms.
However, a number of applications are now emerging for which excellence in mechanical performance is not the main prerequisite, but where sialons, nevertheless, are candidate materials.
Thus the compound LaTaON2 displays a deep red colour and proceeding through the rare earth series in increasing atomic number systematically changes the colour from red to green.

In [4] Haddar et al. present a procedure to obtain an initial configuration based on grain sizes and Monte Carlo simulations.
The analysis was continued until the number of load cycles exceeded 80000.
The number of load cycles and the corresponding crack lengths of 5 predominant cracks are depicted in Fig. 7. 5.
Fig. 5: Configuration after 85000 cycles Fig. 6 (right): Number of casting cycles and penetration depth of 5 cracks over the maximum crack length in the system.
E.g. if the leading crack penetrates 2 mm crack number 10 is about 0.6 mm long and the corresponding number of casting cycles is 17000 6.

Experimental details The microstructure of the examined coatings has been thoroughly investigated in previous studies [3,4], revealing the dispersion of AlN and TiN nanocrystals with a grain size of 10 nm, in a Si3N4 amorphous phase.
During testing the friction coefficient was continuously recorded as a function of the number of sliding revolutions.
In order to estimate the effect of the gradient structure on the lifetime of TiN-based coatings, the duration of the first stage, expressed in number of sliding cycles, was experimentally determined for all the sliding speed values applied and the relevant lifetime factor (L.F.) was calculated, as below: (1) where (TiAlSiN): the duration, in number of cycles, of steady-state wear of the gradient coating, tested at vi sliding speed and (TiN): the duration, in number of cycles, of steady-state wear of the single coating, tested at the same vi sliding speed In Table 1, indicative experimental results are presented for three values of sliding speed; the improved tribological response of the gradient coatings is pinpointed, especially at higher speed values.
In this case, the multilayer character of the films was found also to have a beneficial effect on their wear lifetime, a fact that has been correlated with the repetition number of the essential Ti/TiN pair.
Sliding speed [m.s-1] Friction coefficient Wear track width [µm] Number of cycles to transition zone Lifetime factor TiN TiAlSiN TiN TiAlSiN TiN TiAlSiN 0.02 0.054 0.09 170 220 3420 8613 2.5 0.10 0.056 0.12 120 195 5223 15528 3.0 0.20 0.067 0.22 95 185 6472 22969 3.5 Fig. 3.

The corresponding samples were sequentially numbered for S-1, S-2, S-3, S-0, S-4, S-5 and S-6.
Number Raw material S-1 S-2 S-3 S-0 S-4 S-5 S-6 Alumina Wt.% 69.53 74.53 79.53 84.53 89.53 94.53 99.53 White sand Wt.% 15.47 15.47 15.47 15.47 15.47 15.47 15.47 Fig. 1 XRD pattern of white beach sand.
The samples of theoretical ratio were sintered at 1500 °C, 1550 °C, 1600 °C and 1650 °C for 3 h which were orderly numbered 1-S-0, 2-S-0, 3-S-0 and 4-S-0, and the XRD patterns were shown in Fig. 5.
Acknowledgment This research was supported by the Key Projects in the National Science & Technology Pillar Program (Grant No. 2011BAB03B08), the National Natural Science Foundation of China under grant number 51072186, the National Key Technology R & D Program under grant number 2009AA032501, and the Fundamental Research Funds for the Central Universities under grant number 2011PY0172.
Chan, Control of calcium hexaluminate grain morphology in in-situ toughened ceramic composites, Mater.