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At present, only a limited number of studies reported synthesis of SiC particles reinforced MoSi2 composite powders [13-15] and MoSi2/WSi2 [11] by SHS process.
(Mo,W)Si2 grains, which agglomerated and formed a three dimensional network structure, were observed in this sample.
From Fig.4, it could be observed that the fractured surface of SiCw/(Mo,W)Si2 composite was more tortuous than monolithic MoSi2 and the grains of SiCw/(Mo,W)Si2 composite were smaller than monolithic MoSi2.
It was due to the SiC whiskers deflected the crack and prohibited the growth of (Mo,W)Si2 grains, which was resulting in the significant improvement of flexural strength.
Acknowledgements This project was sponsored by the Natural Science Foundation of Hunan University of Science and Technology under the number E55109.

Introduction Single crystal (SC) superalloys have eliminated all of grain boundaries to form one “perfect” grain, which have led to thermal, fatigue and creep properties superior to conventional polycrystalline and directionally solidified (DS) superalloys[1].
However, the absence of grain boundaries in the SC superalloy also leads to highly material anisotropy which would produce orientation-dependent material response [2,3,4].
The local strain approach is just one of the most representative approaches defined as for k=l,t,d (1) where Ck and mk are the material parameters depending on the temperatures, and Ni denotes the number of fatigue cycles relating to the crack initiation or rupture.
(6) In the fact, uniaxial loading in the characteristic direction of anisotropic materials will produce the same damage as the general multiaxial loading, i.e. the unaxial approach (Eq.(1)) and the multiaxial approach (Eq.2)) have to predict the same number of cycles to failure as follows

And then screen the selected galena, selecting 60 to 80 mesh and 80 to 100 mesh, the two grain size as the samples.
One average radius of galena particles is 0.0950mm measured by microscope whose grain size is 60 ~ 80 mesh, and the other one is 0.0825mm whose grain size is 80 to 100 mesh.
Table 1 The Calculation Results of Reaction Rate of G1 Test Number G1-1 G1-2 G1-3 G1-4 Reaction Rate(mol/s) 1.5818×10-10 3.8036×10-10 7.0506×10-10 1.3164×10-9 (2) When the temperature is 25 oC and pH=2, and the concentrations of Fe2(SO4)3 are 100mg / l, 200mg / l, 400mg / l, the results of Galena oxidation are shown in Figure 2.
Table 2 The Calculation Results of Reaction Rate of G2 Test Number G2-1 G2-2 G2-3 G2-4 Reaction Rate(mol/s) 3.7707×10-11 4.2812×10-11 5.1292×10-11 5.8404×10-11 The impact from temperature on the oxidation reaction rate To determine the reaction temperature of 25oC and 50oC respectively, and the same conditions with the above tests, the test results are shown in Figure 3.

At high temperature, due to shorter creep time, the dimples become small and shallow, but the number of second phase particles with large diameters increases in the dimples.
Creep deformation is pushed by the migration of dislocations and sub-grain boundaries, and blocked by high dislocation density.
Thus precipitation hardening caused by the dislocation occlusion and sub-grain boundaries has great influence on microstructural stability.
Like Laves phase, M23C6 is prior to nucleate and grow in the austenite grain boundaries or laths, but M23C6 coarsening is not evident in such a short creep time.
In Fig. 4, the number of Laves phases obviously increases at 650°C, and the sizes of Laves phases at 650°C are larger than at 600°C, which indicate that Laves phases were influenced by temperature.

Most industries are benefited from the introduction of complex structure using AM which has a wide range of advantages, where the materials are light in weight with increased functionality and reducing the number of parts.AM has reduced the cost of manufacturing and has significantly reduced the design-to-manufacturing time.
Grain refinement helps in lowering anisotropy, defects, and enhances the mechanical properties of elevated strength Al modules which are additively manufactured using laser powder bed fusion.
Although, this process has major milestones in the process of getting desired strength and grain refinement.
Thich could be possible by a hybrid grain refiner which easily refines and increases the mechanical properties of LPBF -fabricated high-strength Al alloys [12]. 2.0 Material Data AlSi7Mg can be used to produce light weight components in the field of automobile and aerospace applications.AlSi7-Mg contains about 6.5% Si, 0.5%Mg and less than 0.2%Fe by weight. 3.0 DMLS Technique The samples were printed using the Direct metal laser sintering technique.
The depth of the indent is measured to determine the Vickers hardness number (VHN).

Thus, a number of surface modification techniques have been developed to fabricate surface titanium matrix composites [7-9].
Recently, much attention has been paid to friction stir processing (FSP), as a novel surface modification technique, in order to minimize casting defects, and to obtain a fine-grained microstructure [10-14].
It is well known that the friction stir zone consists of fine and equiaxed grains produced due to dynamic re-crystallization [1,3,10,13].
Though FSP has been basically advanced as a grain refinement technique, it is also a very attractive process for fabricating composites [11-14].
Finally, a higher micro hardness value was achieved in the advancing side (~470 HV) compared with that in the retreating side (~430 HV), as a result of more number of SiC particles in the advancing side.

A single tungsten carbide particle has been decomposed and broken into a number of small particles in the vicinity of boundary.
A large number of small particles seen here are the intermetallic products of above chemical reaction.
Most of these voids are found in the grain boundary, indicating that there are interfacial gap, which may be attributed to low chemical affinity and thermal stress between matrix and reinforcements.
A microstructure with primary equiaxed α phase grains was formed.
The grain morphology is similar to that observed in sintered pure titanium specimen.

Anand[1] have investigated that one of the important attributes of WC-Co coating microstructure is the extent of decomposition of WC grains during spraying, which is a strong function of the particle temperature in the flame, and can result in undesirable W2C and W phase, in addition to primary WC phase in the coating.
Tab.1 Properties of the powder for HVOF Spraying powder Particle size/μm WC grain size/μm WC-12Co 30~60 2~3 WC-10Co-4Cr 30~60 2~3 The substrate material is Q345 mild steel for coating samples.
The peak numbers and peak intensity of WC in the two images were almost same.
The number, distribution and composition of hard phases in the coating (dispersion strengthening effect of WC hard phase on matrix is most) and distance between the particles (thickness of rich Co binder phase) have a direct impact on the coating hardness.
Though WC-10Co-4Cr coating has suffered a little more hard phases formation, it is considered that the hard phases did not contribute measurably to the hardness of WC-10Co-4Cr coatings since the hard phases grains were very small, and usually attached to WC.

Experimental Program Test Specimens Twelve specimens were designed to study the bond behavior between CFRP sheets and wood, the variable parameters are the force direction of wood, the width of CFRP sheet, the bond length, the number of layers of CFRP sheet and the width of wood block.
Description of Test Specimens Specimen designation Force direction of wood Width of CFRP sheet ()/mm Bond length ()/mm Number of layers of CFRP sheet Width of wood block ()/mm NJ1-1 Parallel to the grain 50 80 1 160 NJ1-2 50 120 1 160 NJ1-3 50 160 1 160 NJ1-4 80 160 1 160 NJ1-5 110 160 1 160 NJ1-6 50 160 2 160 NJ1-7 50 *120/160 2 160 NJ1-8 80 160 1 120 NJ1-9 80 160 1 80 NJ2-1 Perpendicular to the grain 50 80 1 160 NJ2-2 50 120 1 160 NJ2-3 50 160 1 160 *The bond length of the top CFRP sheet is 120mm and of the bottom CFRP sheet is 160mm.
The tensile strength, compressive strength and modulus of elastic along the grain are 70.77MPa, 34.76MPa and 10110MPa individually.

Carbides, presumably M23C6 ranging from 0.05 to 0.5 mm in size, lie, preferentially, along prior austenite grain boundaries and lath boundaries while some are contained in the matrix.
At RT, the highest quasi-saturation stress level is reached for the highest plastic strain range in a lower number of cycles.
At 550ºC the cyclic stress amplitude decreases rapidly at the beginning and then more slowly with the number of cycles without getting a saturation stage.
The obstacles can be the lattice friction, precipitated particles, other dislocations, foreign atoms and grain (or subgrains) boundaries.
The back stress depends on the density of long-range impenetrable obstacles such as low-angle or grain boundaries.