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Acrylic resin has a relatively poor resistance to fatigue fracture, which is mainly responsible for the large number of denture repairs carried out annually [2].
Increasing the amount of initiator increases the initial number of active chains but reduces their mean lengths at the end of the reaction [14].
All surfaces were wet-grinded with metallographic grinding papers which having a grain size of 30µm (P500), 18 µm (P1000), and 15µm (P1200) until edges were smooth and flat.

Meanwhile, the number of bubbles were more, the size of bubbles got bigger and the micro-jet speed of collapse of bubble was higher.
The surface smoothness of casting was less, nano-TiN particles distributed unevenly when micro electroforming without ultrasonic as shown in Fig.5(a); The smoother surface, the higher consistency and finer grains were observed from Fig.5(b) and Fig.5(c) with increasing of ultrasonic power.
The reasons leading to the above results from Fig.4(c): with the excessive ultrasonic power, much more severe the cavitation bubbles collapse, more the number of vortex, higher the speed of vortex, greater impact shock pressure in the interface of electrodeposition near; the nano-particles and nickel ions on the electrode surface that were weak adsorption would be re-washed into the electrolyte because of the larger speed of vortex.

The number of abrasives (Na) doing the cutting at the same time can be written as      = π aSC N V d av a 6 2 0 (6) where C0 is a constant.
Thus, material removing rate (Z) should be in proportion to (F0m - Fc), frequency f and the number of abrasives doing the cutting at the same time Na )FF(fNcZ cm a − = 0 3 (9) As to the grinding dominant mode and erosion mode, they were the major material removing processes to generate the hole surface.
(a) (b) Fig.4 The surface in the grinding dominant area is characterized by (a)machining marks left by abrasives on the wheel (b) many step-like machining marks Surface texture Workpiece Workpiece Debri Chipping Debri Grinding wheel Diamond grain Workpiece Workpiece Surface texture Subsurface cracks (a) (b) Fig.5 The material removing processes of (a) grinding dominant mode and (b) erosion mode Va dc da α xt x y yt crater contact surface particle Fig.6 Erosion model suggested by Hashish 8) was used here to simulate the erosion mode material removing process.

Studies on low-carbon TRIP steel revealed that a large number of researchers have carried their work on the TRIP steel sheet or plate [3, 4].
It seems that a large amount of residual austenite is retained between the laths of bainitic ferrite or at the triple junction of ferrite grain boundaries.
As the carbon content in retained austenite is rather low, the Ms temperature of the undercooling austenite is above room temperature, while the heat-treated steel tubes were cooled to room temperature, a considerable number of poor stable retained austenite prematurely transformed to martensite, and finally resulted in a little higher UTS and lower EL.

Preheating temperature can make up the lost heat, improve the temperature of copper plate before the FSW process, achieve the refining grains, and then obtain a high quality welding joint.
A number of FSW experiments of copper to the aluminium alloy were carried out to obtain the optimum parameters by adjusting the rotational speed of the tool and the welding speed in the range of 600-1400 rpm and 20-80mm/min, respectively.

An algorithm of fuzzy trustworthiness-involved role based access control is developed to implement fine-grained security management and access control of MES.
The Program number is 2011BAF13B04.

Shoot line Yan to cast light a table method(XRD) and scan an electronic microscope method(SEM) with the X, and deeply shoot an electronic microscope method(TEM) to carry on token to the TiO2 powder sample of making,[1] result enunciation titanium sour D ester water solution method legal system have of TiO2 catalysts is the Rui titanium mineral type structure, grain the path be not the biggest over 50 nms.
Because the plate by second boiling distilled water for a while, the pore water can dissolve sodium sulfate in distilled water twice, so that the gap plate number increases, the proliferation of beneficial oxygen; plate muffle furnace at 350°C Heating 30min, so that PTFE emulsion distribution, which will help create holes; into acetone dipping 10h, is conducive to the plate hydrophobic and surface treatment (degreasing).

The aim of research is an exposure of features of electrochemical anodic behavior of pseudoalloy of WC-Co for development of effective method of his dissolution, receipt of tungsten oxides, and also electrosynthesis of tungsten powder with certain grain-size distribution.
The study of the morphology of tungsten powder samples allowed to determine the numerical grain sizes.
It was found that the main grain size is up to 20…30 μm (Fig. 6).
To increase the number of nuclei on a cathode surface followed by the formation of fine powders, the current density must be increased from 1.0 to 12.0 A∙cm-2.

On the other hand, the solidus temperature must not be overcome in order to avoid liquation of lowmelting constituents (eutectic, in particular) and grain boundary regions.
Moreover, it has to be considered that the Biot number concerning the problem of a massive cylinder cooled in water is large (simulating the extrusion heat treatment process) and does not allow for a lumped-capacity solution [18].
Elongated grains aligned along the extrusion direction (vertical direction in Figure 1a) are clearly visible in longitudinally sectioned samples together with stringers on Fe, Mn and Si rich intermetallics.
From transversal samples (Figure 1b), a transversal grain size ranging from about 50 to 100 m can be observed.

An example of a processed area on 5083 cast aluminum alloy (8mm thick) is shown in Fig. 5. 8mm Fig. 5 Macroscopic aspect of the FSP processed area – 5083 cast aluminum alloy In addition to an obvious finishing of the grains in the processed areas (which was more evident in the cast alloys), there were obtained: - significant improvement of the degree of local deformability in the processed area (e.g. up to 100% at the AlSi12 alloy); - increasing the hardness of the material in the processed area (up to: 40% in aluminum 6082, 30-45% in aluminum 7075, 65-80% in CuSn10 bronze, 20-40% in AISI 304 -X5 CrNi 18 10 stainless steel) compared to the base material; - improvement of tensile strength compared to the base material (e.g. up to 30% in CuSn10 bronze).
FSW welding in protective gas environment and FSW welding underwater are of great interest worldwide, as these welding methods are intended to solve a number of technical and technological issues related to the joining of metallic materials with characteristics and properties which require that the joining process is carried out under special conditions (protective gas environment), or which are exploited under certain working conditions (under water).
The use of the SFSW underwater welding method aims to obtain advantages over FSW welding: avoiding overheating of tools and of materials to be joined during the welding process, with the scope to obtain a finer grained structure and thus better mechanical properties, reducing the development of the intermetallic compounds, of the residual stresses and deformations at welding, as well as reducing of welding defects.
Conclusions · The extraordinary qualities of the friction stir welding process FSW, allowed the development of new processes, based on the FSW process principle; · FSP processing can be applied to metallic materials (e.g. aluminum alloys, copper, steel) in order to produce local modifications of the materials microstructure and to improve some mechanical characteristics in the processed area; · Severe plastic deformations and solidifications occurred due to the thermal cycle during FSP processing, could have as a result the formation of a fine and homogeneous microstructure of the processed area; · As a result of FSP processing, the finishing of grains in the processed area can be obtained, the deformability degree of the processed material, the hardness, respectively its mechanical properties can be obviously locally improved, compared to base metal (depending on the characteristics of the base material approached)