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Welding is known to create tensile residual stresses, promote grain growth, recrystallisation and softening in the heat-affected zone (HAZ) [6,7], and to introduce defects that act as stress concentrations and preferential crack initiation sites.
A frequency of 1 Hz was used for all fatigue tests and the number of cycles to failure (N) was recorded for each specimen.
The number of cycles to failure (N) was recorded for each stress range (Ds) at the end of the test.
The HAZ and weld metal, characterised by large grain sizes and coarse second phase particles, were therefore found to be more prone to pitting than the base material [16].
As expected, the number of cycles to failure (N) increases with a decrease in the applied stress range (Ds).

The alloys of titanium are few in number but have been categorized as being both a viable and attractive choice for corrosion-resistance and performance-critical applications.
The grains of the alpha phase (light in color) were well distributed through the matrix of the transformed beta phase (dark in color).
The large volume fraction of the alpha grains was predominantly nonuniform in both size and shape.
The cyclic fatigue test is the most widely used technique to establish the endurance limit of a metal by essentially determining the variation of maximum stress or stress amplitude with fatigue life quantified by the number of cycles to failure (Nf).
The alloy in the annealed condition has an alpha plus beta microstructure with the alpha grains of varying size and shape being well distributed through the transformed beta matrix. 2.

It has been observed that irradiated UO2 undergoes swelling (attributed to the accumulation of gaseous and even nanoscale solid-like fission products) as well as polygonization – the division of each grain into 104 – 105 sub-grains, especially at the peripheral regions subjected to high burnup [23, 24].
Changes to the structure and porosity of the grains, along with the formation of defect clusters and dislocation loops have also been observed [25, 26].
As the knock energy increases, the cooperative displacements become more prominent as exemplified by the four peaks with the 10 keV knock, which is double the number observed for the 2 keV knock.
The histograms are normalized by the number of ions in their respective groups.
Uberuaga, Efficient annealing of radiation damage near grain boundaries via interstitial emission, Science 327 (2010) 1631-1634

The influence of an increasing number of freeze-thaw cycles on capillary absorption of water is studied first, then chloride penetration before and after exposure to a certain number of freeze-thaw cycles was determined experimentally.
For all five types of concrete ordinary Portland cement Type 42.5, river sand with a maximum grain size of 5 mm, and crushed gravel with maximum diameter of 25 mm were used.
Strength of concrete type C decreases with increasing number of freeze-thaw cycles.
Figure 2: Relative dynamic elastic modulus as function of the number of freeze-thaw cycles.
Figure 3: Capillary absorption of concrete type A after different numbers N of freeze-thaw cycles.

However, for bending strength, when the number of elements in model is less than about 9000, there exists obvious size effect, with the increasing of the number of the elements, the size effect will become less and less until disappeared.
The value of fracture toughness decreases with the increasing of the number of the model elements.
Generally, ceramics are polycrystalline, the factors influencing the mechanical properties of ceramics are significant and the distribution of crystal grain and porosity as well as the flaws of crystal lattice in materials.
For every model, we kept the ratio of height to width constant and increased the number of model elements gradually.
The biggest uniaxial compressive model used here is 0.9×1.8mm (the number of particles is 12032), and the biggest three point bending model is 2.7×0.54mm (the number of particles is 10828), the smallest uniaxial compressive model is 0.08×0.16mm (the number of particles is 95) and the smallest three point bending model is 0.4×0.08mm (the number of particles is 237), as shown in Fig.2

In the early deformation stage, SS-dislocations easily disappear through the dislocation interaction and movement to grain boundaries or surface.
(2) � Although a part of dislocations disappears due to the dislocation interaction and movement to surface or grain boundary, the number of stored dislocations should be proportional to ρm.
This suggests that a very little movement of a huge number of dislocations can produce a reasonable plastic strain that affects elastic proportional limit and 0.2% proof stress.

The plan allows studying the effect of each factor on the response variables, as well as the effect of interactions between factors on the response variable at the least number of experiment runs.
When a visible failure area was detected, the number of thermal cycle was recorded and defined as the number of cycle to failure.
Fig 5(b) shows the number of thermal cycle when peeling of the coating layer was observed.
With the increasing of thermal cycle, the number of spalled pieces increases.
This cracks spread to the center of the surface and take place round the grain of splat (shown in Fig. 7 ).

With the increase of Nd, the number of spherical I-phases is reduced and rod-like phases increased.
There are a large number of rod-like phases in the matrix and spherical I-phase is correspondingly reduced.
At the same time, there is different distribution of the enrichment of Nd atoms on every crystal plane of formed tiny quasicrystal grains.
Adding 5% Nd, there is the largest number of spherical I-phases distributed evenly in the matrix.
With the increase of Nd, the number of spherical I-phases is reduced and rod-like phases increased

As for Transdniestr, increased lithium content (up to 0.16%) is determined within thin-layered fine-grained feldspar-quartz sandstones.
Lithium ore is light-grey, almost white, fine-grained rock of massive or not clearly maculose structure (sometimes maculose-band structure) consisting mostly of interconnected and interblending quartz-microcline-albite-petalite and quartz-microcline-albite structural-mineral complexes being characteristic metasomatic formations of metamorphosed original pegmatites.
The height of a grinding chamber and a number of passes of the material through it determine L value.
Obviously, crystallites are formed in the mineral due to the destruction process within the high-angle boundaries of the grains.
Mechanochemical ore activation for complete or partial release of mineral grains. 2.

The commonly used metals are polycrystalline, because each grain orientation is different, apart from this, the microscopic and macroscopic defects such as the dislocation, mixing and second phase exist, there is anisotropy and heterogeneity in polycrystalline.
And the fatigue damage degree of base is proportional to the number of stress cycle.
We assume the number of stress cycle which is reached when the base is damaged under a certain level stress is.
The number of stress cycle is.
(2) As Eq.2 shows, is the number of stress cycle, is the number of stress cycle when the base is damaged.