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The microstructure of the sintered rod of nicrosil is a single-phase solution with a grain size of 8 to 40 µm, and a single-phase solution with a grain size of 6 to 15 µm of the nisil rod.
The number of pores on microsections of sintered rods Pore size Up to 50 µm From 50 to 75 µm From 75 to 100 µm Over 100 µm Nicrosil 86 1 3 0 Nisil 102 5 2 1 In the study of specific differential thermal EMF (αe) of thermocouple welded from sintered rods, it was found that in the temperature range from 0 to 100 oC value calculated from the experimental data coincides with the theoretical value (αt) which was estimated according to GOST R 8.585-2001 and is: αe = αt =0.027 mV/K.

Introduction In consideration of pyrotechnic composed by oxidant, combustible agent and adhesive is a self-contained oxygen system as oxidant providing oxygen required for combustion[1], it can produce a large number of high temperature gases and solid residues which have a certain sound effect through underwater continual and steady combustion.
Pyrotechnic which is composed by oxidant, combustible agent and adhesive is compressed into grains of which density is 1.8 g/cm3, diameter is 18 mm , weight is 5 g installed in the spray cavity and placed together with the resonant cavity which is located on the same axis with pyrotechnic charge nozzle.
Fig. 1 The diagram of test sample, including grain, spray and resonant cavity Experimental platform.

In the micro milling experiments, the super-fine-grained tungsten carbide precision micro milling cutter with a diameter of 500 micron were used in the machining experiments, of which the geographic parameters is shown as Table 2.
Table 2 Geographic parameters of micro milling cutter Cutter Diameter Core Diameter Number of Flutes Radial Rake Angle Helix Angle Radial Relief Angle Axial Relief Angle Edge Radius Tool Length 0.5mm 0.4mm 2 7° 30° 10° 10° 2μm 1 mm Experimental Results and Discussions.
Fig.6 Micro milling force （D=500 μm，n=30000rpm，ap=5μm，vf=5mm/s） Fig.7 Effect of feed speed on milling force Conclusion The finite element simulation model of micro cutting Elgiloy alloy was set up for research the effect of feed rate on the micro cutting force, meanwhile the experimental study on the milling force of the precision micro milling Elgiloy alloy was carried out using an ultra-precision micro milling machine tool with a 500 micro diameter super-fine-grained tungsten carbide precision micro milling cutter.

As high EO coefficients will allow for smaller size devices and lower operating voltages, a growing number of investigations have been focusing on PLZT thin films to achieve high optical responses.
Fig. 2(a) reveals that the films are crack-free, consist of round grains with a crystalline size of approximately 125 nm.
These characteristics, i.e. fine grain size and fibrous columnar structure are very advantageous in increasing the resistance to cracking [[] C.

Based on a large number of experimental results, the mechanisms of reactive-element effects have been reviewed by several authors [1-5].
The as-deposited coatings were nanocrystalline with grain size less than 100 nm [11].
The two effects are related to the segregation of RE ions to the scale grain boundaries and the metal-scale interface.

Therefore, rapid heating is available and the bulk compacts with fine grain microstructure can be obtained [17-19].
When the TiB content was increased to 70%, both the number and the size of the micro-pores in the TiB-Ti/TC4 composites increased significantly.
Whereas the tensile strength decreased rapidly when the TiB content increased from 50% to 70%.In addition to the effect of the relative density, the grain size also plays significant role in the tensile strength.

BMGs have homogeneously long-range disordered structures[21, 22] without defects like grain boundaries or dislocations, that could slightly modify corrosion resistance of Zr-based alloys compared with their crystalline counterparts[23, 24], but prominent enhancement of corrosion resistance of these alloys mainly depended on the electrochemical properties of the elements instead of their structure[10, 25, 26].
Due to a lack of crystalline defects like dislocations or grain boundaries, structurally homogeneous BMGs could form a uniform passive film without nucleation sites for corrosion.
Many relative studies [10, 11]demonstrated that a number of Zr as well as some other elements was detected by EDX or AES on uncorroded region of alloy surface of Zr-Cu-Al-Ni system alloys after polarization, indicating that uncorroded region mainly consisted of ZrO which formed passive film.

This is associated with the Cr depletion around the grain boundaries.
Partridge et al. [2] analyzed SG tube failure data for a number of plants in terms of whether or not H3BO3 mitigates IGA/SCC.
Crack initiation and propagation appeared as IGSCC along the grain boundaries.

Introduction Magnesium alloys present a number of interesting properties, such as high specific strength, good castability, low density, etc.
The as-cast microstructures of CaO added AZ31 Mg alloys are characterized by magnesium grains, grain boundary eutectic phase of Mg17Al12 and Al2Ca.

It was found from Fig.2 that neither the grain size nor the dendrite arm spacing as well as their shapes were obviously changed by various homogenizing treatments.
There were a lot of black dots on grain boundaries and interdendritic areas in the as-cast (Fig.1) and the homogenized microstructures at 360ºC even after 24h heating(Fig.2, d), some dots segregated to form black areas.
The black dots in the samples homogenized at 400ºC and 440ºC were much less than those in the sample homogenized at 360ºC, and with the heating time increase, these dots become to be less in number but big in size, which is more obviously at 440ºC than at 400ºC (Fig.2, e to h, i to l). 400� m Fig.2 Microstructures of ZM21 alloy after homogenizing treatments a: 36��™�� b: 36��™��� c: 36��™��� d: 36��™��� e: 400�™�� f: 40��™��� g: 40��™��� h: 40��™��� i: 44��™�� j: 44��™��� k: 44��™��� l: 44��™��� Fig.3 Macrostructure of samples after homogenization( 360�� (Electrolytic polishing, 2 voltage, 10s, phosphoric acid 33.3% + alcohol 66.7%) 400wm 400wm 400wm 36��™��� 36��™�� 400wm 36��™��� 36��™��� Fig.4 was the micro-hardness vs homogenizing time curve and average relative error of micro-hardness vs homogenizing temperature curve, every micro-hardness value was the average of 5 measuring points, the diversity of