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A mechanism is proposed in which the ultra-fine grain structure of the surface layer produces an anodic activation and the potential difference between the surface layer and the bulk provides and increased thermodynamic driving force for corrosion.
Anodic activation might result arise from residual stress in the deformed layer and/or the greater number density of grain boundaries.
Samples which had been caustic etched prior to PVB coating exhibited a small number (ca 1 per mm) of filaments which propagated slowly away from the defect, reaching a length of < 1.5mm after 100 hours.
SHE and consisting of a large number of unresolved FFC filament heads moves away from the defect at an approximately constant rate.
SHE develops, comprising a large number of unresolved filament tails where the coating is delaminated and corrosion product is visible.

Magnetostrictive Properties of TbxDy1-xFey (x=0.3, 0.33; y=1.05, 1.36, 1.65) Composite made by Directional Solidification and Polymer Infiltration Oh Yeoul Kwon a, Jong Chul Kim b, Young Dong Kwon c, Dae Jin Yang d, Se Hoon Lee e, Zin Hyoung Lee f Dept. of MSE, KAIST 373-1, Guseong-Dong, Yuseong-Gu, Daejeon , 305-701, Republic of Korea aohykwon@kaist.ac.kr, bforjckim@kaist.ac.kr, cydkwon@kaist.ac.kr, ddj_yang@kaist.ac.kr, esh_lee@kaist.ac.kr, fzhlee@kaist.ac.kr Keywords: Giant magnetostriction, Terfenol-D, PIGAC (polymer infiltrated grain aligned composite).
Introduction Monolithic Terfenol-D showing a giant magnetostriction has been received considerable attention in fields of transducer and actuator for a number of years.
Recently, we have developed a new process called by Polymer Infiltrated Grain Aligned Composite (PIGAC) [3].
As RE:Fe ratio is approached to stoichiometric value, the maximum magnetostriction increases because of the decreased amount of the eutectic phase at the grain boundaries, which inhibits the domain rotation by some mechanism, such as production of residual stress [7].

It carried out the flow field analysis of blast nozzles of different structures, with the thought of CFD and computer simulation, it can analyze the dynamic and static performances of grain conveniently and efficiently [1].
Owing to the small volumetric loading rate, it is no need to further confirm two phase flow model through stokes number, only consider the effect on fluid, not consider the influence of particles on fluid, it adopts discrete phase model complying with the Euler-Lagrange method [3].
Definition granular Reynolds number Rep is：，as for 80 mesh SiC abrasive，Rep =25120，therefore, the flow condition of particles within the nozzle is turbulent flow condition.
Through imitating and simulating the velocity of cone sand-blast nozzle every 5° from 10° to 70°,it turned out that the abrasive export maximum speed of cone sand-blast nozzle is bigger than the abrasive export maximum speed of hole blast nozzle, besides, the distribution of abrasive grain in the sand jet cross section is more uniform; Under the same conditions, the best inlet cone angle is 10º to 30º, the export maximum speed of abrasive grain of cone sand-blast nozzle around 20° is Vmax=90.16m/s, which is equal to the result of blasting test results.
This is because of the existence of inlet cone angle, which made the erosion angle of abrasive grain decreased, it decreased the impact force.

Microstructure is bimodal with globular volume fraction of 0.4 and primary α-phase average grain size of 7.4 μm. 20 µm Figure 1.
The average grain size has been evaluated by the random secant method according to GOST (State Standard) 21073.3-75.
The globular grains have been identified by a ratio between the longitudinal and transversal sizes of no larger than 3:1.
The volume fraction of globular α-phase in the bimodal structure has been determined by computing the area occupied by globular grains using an overlain mesh with a cell size of 5 μm.
The objective function is the following expression: Φ=1Kj=1K1Nji=1NFij-fijFij2, (3) where K – number of flow curves; N – number of points approximating the flow stress curve; Fij – an experimentally determined force at a point, N; fij(p) – calculated force at point, N.

Forward propagation: In the first step, the calculated output data is compared with the given output data and the output differences are aggregated to generate an error function E defined as: (4) Where p is the total number of the patterns, k indexes the output units, Dpk and Opk are the desired and the calculated output for the kth neuron, respectively. 2.
According the practical question of this paper, three input of network include solid content of Al2O3 ceramic slurries (w), centrifugal acceleration (v), sintering temperature (T) and two outputs include fracture strength (σ) and fracture toughness (KIC) of Al2O3 ceramic.The number of neurons present in the hidden layer can determined by the empirical formula [6] and is seven, so the final network structure is 3×7×2.
This is mainly because with the increase of , the irregular particles of Al2O3 green compacts grow up and turn into large grains.
These large grains are closely bonded together and have more contact area, inducing a decrease in the porosity and an increase in σ and KIC.
When the samples sintered at 1550℃ for 2h, fewer grains preferentially grow into very large size compared to other grains, inducing overfiring phenomenon.

The number of thermal cycle was recorded.
Table 1 Composition of Fe-V-W-Mo alloy (wt. %) Number Modifier C V Cr W Mo Co Modifier remains 1 No 1.88 3.77 7.12 4.89 5.05 3.13 No 2 RE-Mg 1.91 3.84 7.12 5.06 5.04 2.98 0.10Ce, 0.05Mg Results and Discussion Influence of RE-Mg on the Structures of HSS Roll.
Compared with Fig.2(a), it is found that austenite grains and eutectic structures change greatly into fine structures and there are a large amount of small lump carbides with the addition of modifier elements.
After modification, eutectic carbides become a discontinuous network and grain, as shown in Fig.2(b).
Crack propagating along carbides is hindered by matrix and crack must pass through matrix from one carbide grain to the adjacent grain.

Since the preparation of TiAl alloys by casting results typically in a polycrystals with large grains of more than 1mm in size, statistical distribution of lamellae orientation in grains within the gauge length of the specimens may be different for different specimens and contribute to important scatter of fatigue life, which is usually reported for the TiAl alloy [7].
The microstructure of the material is lamellar with some single g-phase islands close to grain boundaries covering of about 3 % of the volume.
Minority phases b and B2 were observed either in regions between lamellas of g and a2 phases or in regions close to grain boundaries.
Cyclic behaviour The evolution of stress amplitude sa with the number of cycles N in constant strain amplitude cyclic test, i.e. the cyclic hardening/softening curves, is shown in Fig. 1.
In cycling with low ea (0.24 – 0.30%), cyclic softening occurs at the onset of the test, up to about 1% of number of cycles to failure Nf and then the stress amplitudes saturates.

Magnetite usually appears between the grains of hematite.
The dark gray amorphous phases between hematite grains are slag phases.
For samples with low expansion rate, the amorphous phase content between hematite grains is relative high, which indicates to promote the liquid phases can effectively prohibit the abnormal expansion of pellets[5].With the increase of liquid phase, the alkali metal ions that entered liquid phases increase and thus the affect of alkali ions on expansion of pellets was alleviated.
During the roasting process, the liquid phase between grains of hematite formed a space baffle to the growth of hematite whiskers [6].
The porosity of all the 9 experiments ranges from 25% to 30%.When bentonite proportion is 3.3% (3#,4# and 8#),number of the pores linking together is relatively small, but when the bentonite proportion decreases to 1.3% (1#,5# and 9#),the number of pores linking with each other growth sharply.

The FTIR spectra of the calcined D-HAp sample provide a number of spectral details indicating some changing have been occured.
The intensity count of diffraction peaks is increased owing to the detection of more number of diffracted rays developing from the larger number of same group of planes.
It is only possible when the number of crystals as well as crystalline domain planes is increased.
As a result, the more number of crystalline pure D-HAp phase formations is revealed at 800 °C compare to 500 °C temperature as the peaks become more intense at 800 °C [14 ].
In the calcined D-HAp samples at 500 oC, the microstructure composed of various size grains, most of them were large and irregularly shaped grains of a diameter approximately 5 mm, but in the calcined sample at 800 oC, there were identified regularly shaped grains resembling a sphere with a diameter of approximately ≤ 1 mm.

The grain size of chromium diboride powder ranges from 2 to 7 μm.
The pronounced contrast of the particles in the backscattered electron (BSE) mode highlights differences in the atomic numbers of the constituent elements.
The image was captured in backscattered electron (BSE) mode, which enhances the contrast between components based on differences in atomic number, thereby highlighting variations in chemical composition.
Diamond particles are likely represented as bright regions with well-defined boundaries and high intensity, which can be attributed to the high atomic number of carbon in its diamond form.
Liu, Grain size dependence of wear resistance of polycrystalline diamond compact, J.