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Because the σ phase is easy to precipitate at the grain boundary, the σ and Laves phase line intersections are avoided in the composition design, and the appropriate aging temperature is determined to avoid precipitation of σ phase.
It can be seen from Fig. 7(a) that a large number of fine, dispersed secondary phases are precipitated on the martensite lath.
Ju, Grain boundary embrittlement by μ and σ phases in iron-base superalloys, Acta Metallurgical Sinica 17(1) (1981) 1-114

The alloy microstructures, used in medical applications, is define by crystallographic orientation, texture, morphology, distribution, size and number for existing phases [5-6]. 2.
The fragile break produce slicing in a plan perpendicular to request plan and have crystalline aspect (the fracture are initiate on grain limits with appearance of cleavage plans).
The micrographs for CoCrMoSi6 alloy highlights, at big magnitude (1000X and 2000X), small areas with carbides in matrix and the alloy structure becoming with a non-uniform grains and an inter-dendritic eutectic, with different crystallographic orientations.

.% Al in a number of alloy systems belonging to metal-transition metal (TM) and rare earth (RE) [4].
This would effectively control grain growth [14].
The fact that the heat released in those transformations (-54.2 J/g) is a little smaller than the heat released during continuous heating (-58.9 J/g), reinforces that the behavior is typical of nucleation and growth of grains.

During the process of mechanical alloying, a large number of defects are created by large plastic deformation, such as vacancies, dislocations and grain boundaries that will be accumulated in the milled powder.
Zheng, Thermodynamic consideration of grain refinement of aluminum alloys by titanium and carbon, Metallurgical and Materials Transactions A, 1991, 22(12): p. 3071-3075.

The resulting sequence can be written as A1B1C1A2B2C2A1… where the letters (ABC) indicate the Ni Nb geometric position of the atoms and the numbers (12) their chemical nature.
Results and discussions In the present study the observations made on grains containing quite large " precipitates are reported, since SFs are commonly observed in such large precipitates.
In the different grains, that were objects of study, the presence of the three possible " variants in the form of circular plates (about 100 nm in diameter and 20 nm thick) was noticed.

Density, being a measure of the coating’s volume porosity, reaches value of ~90% on average while YM demonstrates more modest numbers because it is sensitive not only to the porosity, but also to the grain-to-grain contact quality (cohesion).

Nanodiffraction of the small grains showed a randomly oriented grain structure.
For higher annealing temperatures the small voids inside the platelets will coalescence, increase in size and reduce in number density. 1000 nm1000 nm1000 nm1000 nm1000 nm1000 nm1000 nm1000 nm 1000 nm1000 nm1000 nm1000 nm1000 nm1000 nm1000 nm1000 nm 100 nm100 nm100 nm100 nm100 nm100 nm100 nm100 nm Figure 3. a) Large platelets surrounded by strain fields formed deep into the low n doped sample S1, observed close to [111] zone axis, b) After 1 hour annealing at 600 °C all hydrogen is gone and only boundary dislocations and small voids remain, observed close to [100] zone axis, c) Almost no platelets are visible in S3 after 1 hour annealing at 600°C.

A number of compositions based on BaTiO3 (BT) has been investigated in respect to their relaxor properties [2].
No significant difference in average grain size for ceramics with various LMT content was observed.
Unlike in BT-based solid solutions [6,10], any sign of abnormal grain growth have not been revealed in NBTLMT.

Under the wave and the tide, the fine grain granules were constantly brought to the offshore, and the rough granules were left.
Table 1 Parameters of silt in the Yellow River Delta Speci- fic Gravity Water content (%) Wet unit weight (kN/m3) Void ratio Saturation (％) Li- quid limit (％) Plastic limit (％) Cohesion (kPa) internal frictio- nal angle compres- sion coeffi- cient (Mpa-1) grain size composition (%) sand soil clay 2.69 24.41 19.88 0.68 96.78 27.93 19.7 7.36 33.65 0.11 4.2 87.6 8.2 The W3ZB-20 type triaxial apparatus was taken to finish this test, which has stress control mode and be used to simulate the sine wave loading, and the test vibration frequency was 1Hz.
(1) The silt soil's axial strain was increased gradually along with the number of the circular vibration, and the relationship between them was basically linear

The Pharma grade ZnO contains many rods and grains whereby the rods are 70-200 nm in diameter and 200-600 nm in length.
The White grade contains mostly ZnO rectangular grains with width of 100-250 nm and length of 150-600 nm in dimension.
A number of studies have suggested, two mechanisms for the interaction between ZnO and bacteria that are (i) the production of increased levels of ROS, mostly hydroxyl radicals and singlet oxygen [10], and (ii) deposition of the ZnO on the surface of bacteria or gathering of ZnO either in the cytoplasm or in the periplasmic region causing disruption of cellular function and/or disruption and disorganization of membranes [11].