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Introduction It is well known that under many circumstances when ferroelectric ceramics are switched under high a.c. field, the switched charge and the induced strain decay with increased number of cycles [1~3], which is the so-called electrical fatigue.
In Fig.2, the normalized remnant polarizations Pr were plotted against the number of the cycles for different magnitudes of the applied sine wave electrical field (50Hz).
As the different crystals cannot be switched simultaneously during the polarization reversal [7], so generates stress concentrations at the grain boundary.

The addition of manganese controls the grain structure which in turn results in a stronger alloy, thus replacing 6061 in many structural applications (Tab.2).
To find a window of joinability, many parameters have to be set: the compression force and its type of solicitation (monotonic or cyclic, with a variable mean value or not), the torsion angle amplitude and its period (thus defining the speed of rotation), the number of cycles, the surface polishing at the interface.
In order to valid this interpretation, a second protocol has been conveyed: a torsion test specimen has been cut through its section and undergoes a compression followed by a cyclic torsion with small angles during a great number of cycles.

Fig.2 Charge-discharge curves of first cycle(a) and variation of specific capacity with number of cycles (b)of the coated(sample B) and uncoated(sample A) LiCo0.02Cr0.02Mn1.96O4 cathode materials at 20˚C Fig.3 Charge-discharge curves of first cycle (a)and variation of specific capacity with number of cycles(b) of the coated(sample B) and uncoated(sample A) LiCo0.02Cr0.02Mn1.96O4 cathode materials at 55˚C Fig.3 shows that the electrochemical performance of the coated(sample B) or uncoated(sample A) LiCo0.02Cr0.02Mn1.96O4 cathode materials is evident difference at 55˚C.
This indicated that the surface of LiCo0.02Cr0.02Mn1.96O4 grains had some changes.

(1) with pmacro the overall macroporosity, pmicro the remaining solid matrix microporosity, m a morphological dependent parameter, Nc the average number of closest neighbours for each matrix grain, and σr0 the compressive strength of the fully dense material, i.e. with pmicro = pmacro = 0.
Ceramic blocks always contain a large number of natural flaws (microcracks, little holes, mechanical weak points).

Adequate procedures are the reduction of the porosity or the reduction of the number of large pores by warm pressing, high temperature sintering or sinter forging as well as suitable heat treatments [3].
In the as sintered state a relatively homogeneous structure is found consisting of upper bainite with very fine line-like carbides within the bainite grains.
As ultimate number of cycles NU = 10 7 cycles were assigned. 103 104 105 106 107 108 100 200 300 400 500 as sintered R = -1 F = 45 Hz 90% 50% 10% 255 MPa 280 MPa 300 MPa σ *a,R [MPa] Nf 103 104 105 106 107 108 100 200 300 400 500 as sintered R = 0.1 f = 45 Hz 90% 50% 10% 228 MPa 195 MPa 170 MPa σ *a,R [MPa] Nf Fig. 1: Geometry and dimensions of the bending specimens.

Meanwhile, for micro-size laser beams, the size of the laser-target interaction zone is of the same order of magnitude as the grains of the most commonly metals.
Besides the basic parameters, such as laser intensity, spot size and the number of pulses etc, considering the anisotropic of single crystal material and crystal orientation, the direction of shocked line and spacing between successive pulses are also have a direct affect on the dent geometry and the characterization of residual stress. 4) Others.
As shown in Fig. 3, the pulse duration was 50ns, spacing between successive pulses along a shocked line was 25µm, and pulse numbers were 3 on each shocked location at 1 KHz pulse repetition rate.

A recent study shows that the ductility has been effectively improved in Cu-doped Ni-Mn-Ga alloy under the situation of single phase via strengthening grain boundaries [9].
All these energies are normalized by the number of atoms.
As seen in Fig. 2(a)-2(c), comparing the total up and down densities, we note that the differences of the magnetic moments of these materials are determined by the difference between the up and down electron number in the bonding region below EF.

Initially, they were sun dried, ground, and classified in a granulometer by sediment grains of less than 0.42 mm.
From the results, a number of samples were selected for analysis by electronic scanning microscope with a view to comparing the microstructures of the acid serum-based mortar [8].
Given the sheer number of structures on the planet is taken into account, in particular in developing countries, the method would allow for the effective reuse of 60,000 tons of acid serum per day.

Dividing the number of teeth is 5.
Each tooth sequentially numbered, then teeth scanning sequence: 1 - 6 - 11 - 16 - 21 - 2 – 7… The same side surfaces of the gear can be completed cladding by 23 times dividing.
Grain forming and have no chance to grow up in rapid solidification[2].

Then a large number of primary αphases dissolved and a few had been kept after the flat billets were secondary forged and rapidly cooled.
In addition, the fast cooling process also caused the alloy grains to fail to grow, So the plasticity is better than that of the show cooling process.
8 ≥ 20 ≥ 635 ≥ 50 ≥24 ≥855 930/ 1130 ≥ 8 ≥ 25 ≥ 635 ≥ 50 ≥ 32 Note: persistent temperature 500℃, stress 470MPa Fig. 3 Transverse strength at room temperature Fig. 4 Longitudinal strength at room temperature As mentioned above, although the comprehensive properties of the flat billets produced by the four processes all meet the standard requirements, the mechanical properties of the blank forged by the 1-4 process are the best (see table 2), and the microstructure also meets the blank requirements of the forging.Since the final forging is used as a bearing part, the higher the strength, the better, so in conclusion, 1-4 process is selected as the best process for producing blank for frame forging. 3 Conclusion It’s an excellent thermal process for TA15 titanium alloy slab that the first forging temperature is T1 and the secondary forging temperature is T2 with rapid cooling rate after thermal deformation.The flat billets will have 10% primary α phases and a large number