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Numbers of empirical equations based on experimental results have been suggested to calculate the relaxation of compressive residual stress.
Reduction in residual stress as a function of the exponent of the number of cycles, N was proposed by Han et al. [3] as follows: (1) where is the residual stress relaxation, is the residual stress at the first cycle and k is dependent on material softening and applied stress.
Linear logarithmic relationship as function of number of cycles was proposed by Kodama [4] as follows: σNre=A+mlogN (2) Where σNre is the surface residual stress after N cycles.
Samples were rocked through an angular range of ±1.5 deg around mean psi angles during measurement to integrate diffracted intensity over more grains to minimize influence of grain size.
During the subsequent cycles, micro-plastic strains accumulated from cycle to cycle in logarithmic relation to the number of cycles.

It can be expressed by means of the following dependence: (1) EN – electrode negative duration EN+EP – total time of the whole cycle (EP represents the duration of the positive component) The authors’ own research proved that in the case of welding zinc coated sheets, a bigger EN ratio helps reduce the number of deformations and causes less damage to the protective zinc coating [7].
The microscopic metallographic tests revealed slight stirring of the material in the weld area and a relatively small grain growth and phase precipitates in the padding weld and heat affected zone.
No excessive number of precipitates or the presence of cracks or micro-cracks in any area of the padding weld or HAZ were revealed.
The analysis of the microscopic metallographic photographs of the padding welds made with filler metal Al5087 on the base EN AW 6082 alloy revealed that the padding weld has the structure of the AlMg-type alloy with a small number of phase b (Al3Mg2) precipitates.
It was also possible to observe a characteristic Partially Melted Zone with a small number of Mg2Si precipitates typical of aluminium alloys of 6xxx series as well as a considerable grain growth.

Evaluation of a Shoe Cushioning System Using Shock Absorber by Biomechanics Moon Byung Young ILIC, Pusan National University, Busan 609-735, Korea Keywords: Shoe cushioning system, Impact force, Biomechanics, Porous Silica Grain Abstract.
(a) Walk way and GRF (b) Shoe cushioning system (c) SEM of mesoporous grain Fig. 1 Concept and structure of shoe cushioning system Table 1 Data of the participants Participant 1 2 3 4 5 Avg S.D.
Hereafter the more significant result will be able to be obtained through the standardization of the experimental method by collecting many more trained subjects and statistical analysis of the results from a number of experiments.

In addition, inverse pole figures (IPF) were constructed using the method described in [18], showing color maps of the normalized pole density equal to the ratio between the total number of plane normals registered along a given direction to the corresponding number in a non-textured sample in the standard stereographic triangle.
At T = 600 °C the observed number of pores is lower, which means temperature-induced densification occurred.
At late stages of compaction (Fig. 3c), a very small part of the initial number of agglomerates survived hot pressing.
The main difference is that instead of taking the volume diffusion coefficient DV , one has to use the grain boundary diffusivity if grains are small.
In case of a porous media where there are no grain boundaries, the surface diffusion coefficient Ds should be taken instead.

The results show that cycle numbers of crack initiation increase and resistance of thermal fatigue decreases with the rise of notch radius at the upper temperature of 1050°C.
The cycles of crack initiation is the numbers when the crack length is 100mm.
Crack initiation numbers decreases and thermal fatigue property is improved with the rise of notched radius.
The MC carbide of testing alloy has the script-like morphology and continuously distributes in the grain boundary or interdendrite region (Fig. 3).
The cycle numbers of crack initiation raise and resistance of thermal fatigue decreases with the rise of notch radius at 1050°C.

Sulphidation is more complex than oxidation due to the occurrence of a larger number of stable sulphides as compared to the oxides.
This plate easily fell of the surface and unveiled inner part of the scale which was thinner, better adhered and had finer grains.
The predominating part of the surface was covered by very dense, fine grained, tiny and string adhered scale.

Constitutive models Coarse –grained material constitutive model Nonlinear elastic Duncan-Chang E-B model [3]which widely used in China is adopted to simulate the behavior of Rockfill materials. following formula is used when loading: (1) Where is the tangent elestic deformation modulus, and the is the bulk modulus, and is standard atmospheric pressure.
For unloading and re-loaded, substitues in equation (1): (2) Coarse-grained materials internal friction angle φ with the compressive stress change: (3) The material parameters in equation (1) to (3), such as , , , , c,, and can be obtained from large scale tri-axial test.
The total nodes number is 20738and the total elements amount of Maji dam is 20122.

The number of pulses above a given potential threshold (COUNTS) is related to the Barkhausen jumps in the area of the measurement.
BM consists of equiaxed grains finer than those in HAZ.
MBN is sensitive to grain size and residual stresses which affect domain configurations and domain wall pinning sites.

Application of laser heat treatment nitrozomocevina layers without melting the surface allowed to form a structure with high amounts of residual austenite (up to 80 – 100%), crushed grain, eliminate troostite and bainite structure (Fig. 1, b), improve the hardness, ductility and wear resistance of the diffusion layer.
Application of laser heat treatment nitrozomocevina layers without melting the surface allowed to form a structure with high amounts of residual austenite (up to 80 – 100%), crushed grain, eliminate troostite and bainite structure (Fig. 1, b), improve the hardness, ductility and wear resistance of the diffusion layer.
Microstructure nitrocementation layers of steel 18CrNi3Мo (X 400) a – before laser treatment; b – after laser treatment Study of thin foils made of nitrocementation layers with subsequent laser heat treatment at a distance of 0.15 and 0.30 mm from the surface revealed the presence of a large number of selections of various dispersity and shape.

After the deformation the sample was cut onto slices for further structural studies - (a )- number of slices; (b) - place of cuts by a circular saw; (c )-a slice; (d) - the place of a discs cut for the TEM studies The TEM studies were carried out on the samples cut from the slices in the way shown in Fig. 1.
Fig. 3 Highly deformed structure of the B2 phase(a) and a grain with B19'martensite (b) - the diffraction pattern indexed as the [112]B19' zone axis Additionally, in all the samples, regardless the place of which it was cut off, there were microcracks in the TEM foils that were surrounded by amorphous regions (Fig.4).
The applied severe deformation of the NiTi alloy caused the grain refinement and high density of structural defects, mainly dislocations in the B2 structure.