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The number of slits for embedding strands was changed from zero to five, and the effect of slit numbers on the mechanical properties of the assembly was investigated using tensile and bending tests.
The relationship between the number of slits and tensile strength under different rotation and travel speeds is shown in Fig. 4 As the number of slits increased to three, the strength also increased.
This is thought to be due to grain refinement and work hardening due to stirring.
This is due to the grain refinement within the stirring zone.
• An increasing strength tendency was confirmed by increasing the number of strands.

It is known that the microstructural effects of the two mentioned processes can be distinguished because the creep type deterioration can cause cavities along the grain boundaries [2], while the fatigue process causes the appearance of micro and later macro cracks through the grains.
The total lifetime of the tested steel is defined with the number of cycles at which visible (about 0.1 mm) macroscopic cracks appear on the surface of the specimens.
The applied numbers of thermal shock cycles in the present investigation were 0, 100, 300, 530, 1000, 2000 and 4000.
The increase of the number of TSF cycles seems to decrease the slope of the M(H) curves.
Fig. 2 shows the dependence of Barkhausen noise and coercivity (Hc) on the number of TSF cycles.

The circle numbers, stress level and specimen damage were recorded which were listed in the Table 3 and Table 4.
Fatigue test data of the A6 samples Test Method Test Data Up-Down Method [MPa] 50 54 58 62 Circle Number [104] 1000 296.7, 1000, 1000 209.3, 547.9, 731.6, 1000,1000,1000 104.2, 137.9, 231.7 Group Method [MPa] 80 90 Circle Number [104] 90.2，176.7，97.1， 92.4，60.8，113.8 47.0，57.7，45.4， 39.0，43.1，51.3 Table 4.
Fatigue test data of the A7 samples Test Method Test Data Up-Down Method [MPa] 69 73 77 81 Circle Number [104] 1000, 1000 1000,813.7,1000, 673.2,1000 665.3,1000,495.7, 1000,1000 352.2,592.1 Group Method [MPa] 87 92 Circle Number [104] 44.6，60.4，104.2， 106.5，110.3，180.7 22.4，28.2，33.3， 43.2，43.7，71.3 p-S-N Curves.S-N curve is a fundamental data diagram, characterizing material fatigue property.
In surface of fatigue sample, the inclusion, coarse grain and brittleness particles cause stress concentration in microstructure, promote the micro-crack initiation[7].
These phenomena demonstrate that cracks in different crystal face expand forward simultaneously and intersect within limits; when encountering the grain boundary, the forefront of crack is blocked and the direction of its striation changes, the fatigue steps emerge from it is also an important microscopic feature.

They studied equilibrium lattice and grain boundary (GB) self-diffusion in CoSi2 and diffusion during CoSi2 growth via interfacial reaction.
This way, the effect of parameters such as temperature measurement errors, impurity contamination variations, and grain size variations should be negligible compared to the possible effect of interfacial reaction on atomic transport.
Atoms are diffusing only in GBs and the diffusion kinetic is independent of grain size.
Ex situ AFM measurements showed that the surface roughness of the sample after annealing was about 1.5 nm, and that the average grains size was ~ 44 nm, which is in agreement with the thickness of the Pd2Si layer (generally grain size is about the same as film thickness).
KS =for the sample surface, Kb =for the sample bulk, and K = KS + Kb, a being the attenuation parameter expressed as a = exp[-1/lEi cos(w)], with lEi the IMFP of electrons in ML units, corresponding to the pure element i and a given Auger electron kinetic energy E, and ω the emission angle of Auger electrons. n is the number of first atomic planes considered to be the surface, and m is the total number of atomic planes probed by AES.

The number of SPM instruments sold worldwide is around 10 - 20 thousand.
The emission of these electrons shows no atomic number dependence, thus SEI image is a pure topographic image excepting the edge effect.
The SEI image shows the grain structure of the layer, at the BEI image and the Pb grain are bright, and the Sn ones is dark.
SEM images were suitable ideal to measure the orientation, grain size, and homogeneity of the whole 3 dimensional (3-D) structure.
AFM images can provide useful information on surface roughness, secondary grains in a nano-scale and the homogeneity of the structure face of the structure.

TRC is a material composed of a high strength fine grained concrete matrix (aggregate size is less than 1.2 mm) and textile fabrics.
The bond is still governed by adhesion in this area that contains a number of micro-cracks.
Table 4-1 lists the average crack number and crack spacing of each group specimens.
It is clear that T1MS30 has the largest crack numbers, about 2 times than that of T1MS0.The average crack spacing of mid-span is about 7.2 mm, decrease by 42% than that of T1MS0.
Table.1 The average crack number and crack spacing Serial number The average crack number of pure bending section The overall crack number of specimens The average crack spacing of pure bending section[mm] 1-T1MS0 8.33 12.67 12.267 2-T1MS30 14.00 25.00 7.161 3-T1MS60 8.50 13.50 11.974 4-T1MS120 9.30 16.30 10.733 We can draw the conclusion from the above analysis: epoxy resin impregnated and sand covering on the surface of textile can heighten the ultimate bearing capacity of TRC, control the matrix cracking, increase the crack numbers and obviously improve the bond property between textile and matrix.

Major drawbacks are the poor reliability and predictability of SMA elements available from SMA providers - it is not possible to guarantee the stability of the functional stress-strain-temperature responses of SMAs with time, larger strain and stress amplitudes, number of activation cycles etc to the precision required in engineering.
Optical observations of martensitic microstructures on polished surfaces of SMA single crystals or large grain polycrystals have been used since early days as an experimental method for characterization of microstructure evolutions in SMAs.
The elastic strains, εhkl, in particularly oriented grains, called lattice strains further on, are evaluated from the diffraction measured deviations of dhkl-lattice spacings (Eq. 1).
Diffraction patterns (b) are recorded during numbered stopovers (a) along the compression test.
Summary Advanced in-situ experimental methods and approaches applicable to martensitic transformations in SMAs appear in ever increasing number every year in the literature.

In this study, a sample of fine-grained ZrB2 ceramics was investigated under dynamic compression and tension.
The RVE size is established such that it contains a number of voids and crystalline grains providing equal values of statistically averaged physical-mechanical property.
Effective size of fractured cells fractal cluster was calculated by the formula: , (12) where M is a total number of cells in RVE, xki is coordinates of boundaries. . (13) As criterion of RVE fracture corresponded to full loss of the shear strength is (14) where is the minimum number of cells in a probable fracture surface in RVE, j is component of normal vector to fracture surface.
Average value of D calculated by formula , (15) where n is a number of damaged material particles in RVE.
A decrease of the shear strength can be caused by nano-voids in vicinity of triple junctions between ceramic matrix grains and ultrafine-grained ceramics.

The phase transformation and the final microstructure were studied in a pipeline steel grade API-X80 by carrying out a number of physical simulations of the industrial hot rolling schedules.
Tnr, is a critical temperature below which static recrystallization is suppressed or retarded by the occurrence of "strain-induced" precipitation, and pancaked austenite grains are formed as a result of deforming the steel bellow this temperature.
This temperature is considered for the design of the rolling schedule; the finishing rolling should be applied under this temperature to obtain deformed austenite grains which leads to finer final grain size. 800 900 1000 1100 0 50 100 150 200 0,71 0,76 0,81 0,86 0,91 MFS [MPa] 1000/ (T+273) [k] Temperature [ºC] Test C Test B Test A 980 ºC Fig. 1: Determination of the austenite non recrystallization temperature Transformation behaviour.
The bainitic ferrite transformed at higher temperatures presents lower Vickers hardness values, larger grains and absence of martensite/austenite islands.

This material was then abandoned for a number of years due to the production of hydrogen gas at the site of implantation in vivo [17].
A number of mitigation measures have been proposed for the purpose of increasing corrosion rates.
In this scenario, a number of reactions take place which produce iron hydroxide species [22, 25, 29, 37, 38].
However authors also comment that with silver a secondary mechanism may be aiding in increasing the corrosion current namely; the segregation of silver at grain boundaries which limits grain growth [42].
Davies, "Revealing the relationship between grain size and corrosion rate of metals," Scripta Materialia, vol. 63, pp. 1201-1204, 2010