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The technology is quite new and so, investigations have to be performed in order to gain a comprehensive knowledge about effects on numerous material and technological parameters on weld quality and properties.
However, fatigue loading is a very important factor affecting service safety and reliability and that is why a particular emphasis on fatigue resistance together with evaluation of damage mechanisms and affecting factors was put in this work.
Note that investigation of fatigue properties and phenomenon is still missing in some works aimed at laser welding of high pressure pipelines [6].
In that case, the so called K-calibration factor F, which is a function of (a/W), can be neglected [7] and stress intensity factor K can be simply calculated as K = sÖ(pa).
Němeček: Effect of shielding gas on residual stresses and mechanical properties of laser welding of S355 steel, in: Proceedings of EAN 2016 - 54th International Conference on Experimental Stress Analysis (2016).

Non-destructive techniques are rapidly used to control materials’ properties during the manufacturing and using.
Due to the processing differences, water absorption (%), apparent porosity (%) and mechanical properties of these tiles changed and the inspected properties measured conventional techniques.
One of basic ways of measuring elastic properties by wave methods is also by resonance vibration of specimens.
Though porcelain tile production is increasing, stoneware products obtained by last single firing still have the largest share in production, the body or substrate being the determining factor in the mechanical and technological properties of the resulting ceramic tiles.
Schematic of maxima of properties such as strength that is dependent on porosity decreases with increasing firing temperature or time (Fig. 4).Thus, most mechanical (and other) properties increase with decreasing porosity, i.e., with increased sintering [2].

The optimal value of tensile strength was obtained by using the Large-the-Best characteristic of the Taguchi Method to obtain the important control factors of this experiment; a validation experiment was carried out by using the adjusted factors. 1.
A tensile testing machine was used for welded test pieces to test the mechanical properties of interfused heterogeneous plastic materials after ultrasonic was applied.
Method, which suggests to regard about a half of control factors as important factors, and the rest of half as unimportant factors.
According to this table, the S/N ratio of the optimal design has a small error of accuracy. 4.4 Analysis of variance The main purpose is to evaluate the experiment error amount, and judge whether the experimental factors are important factors and the relative contribution of the factors by using statistical verification method.
The four key factors are hardening time, welding time, welding pressure and motor speed.

Among these earthquakes，the 8.5 Haiyuan earthquake in 1920 and the 8.0 Gulang earthquake in 1927 caused serious disasters and the loss of lives and properties was huge[2].
Because of the special characteristics of loess in thickness, geomorphology and soil mechanical properties, etc. the earthquake damages are serious and the range is large.
The peak acceleration, as far as site factors are concerned, is mainly affected by the thickness of soil, topography, conformation and the soil properties, etc.
Among these factors, the overburden thickness and the slope grade are two important factors influencing earthquake damage.
As a result, the influence of these two factors on ground motion amplification was analyzed and the distribution of the peak acceleration under different seismic load was obtained as well.

The research results show that the normal grinding force is the primary factor responsible for the generation of residual stress in grinding ceramic.
The mechanical effect of the grains is to affect the magnitude, the depth of penetration and the gradient of the residual stresses.
Introduction In modern manufacturing, interest in advanced ceramics has increased significantly in recent years due to their unique physical characteristics in their mechanical properties and reliability.
The advantages of ceramics include: a higher hardness and strength, retention of these properties at high temperatures, a low density, a low thermal expansion coefficient, chemical stability, a superior wear resistance and good self-lubrication properties.
The ground material was Silicon nitride (Si3N4) and the properties are shown in Table 2.

The specimens are the engineering steel (SM490B) and their chemical composition and the mechanical properties are shown in Table 1 and 2.
Mechanical properties of SM490B Composition (weight %) Material C Si Mn P S SM490B 0.18 0.55 1.60 0.035 0.035 Fig. 1.
A model for crack growth retardation Determination of overload effect factor.
r p a a* r po Overload affected plastic zone Instantaneous plastic zone S S Fig. 4.
C is an empirical constant affected by the overload ratio.

Introduction Thin hard coatings can be found in many mechanical applications.
Vickers microhardness (Remet HX-1000 Vickers microindenter) was evaluated on the titanium alloy bulk samples before and after the deposition to assess any changes in the mechanical properties induced by the heat treatment at 420°C.
The surface hardness of the alloy was not significantly affected by the deposition process (as received: 271 ± 4 HV0.5; after deposition: 286 ± 4 HV0.5).
The reduction of the applied stress is quantified by a fatigue stress intensification factor Kf calculated for a fatigue life of 200000 cycles.
Comparing it to the lower Kf from the fatigue tests, the notch root plasticity due to the stress redistribution may be supposed to be one of the main factors affecting the fatigue life of the notched specimens, as far as the uncoated ones are concerned [9,10].

In the recent studies it was shown that localized heating during FSW process caused microstructure evolution in the different zones that influenced the mechanical properties in the weld.
The aim of the present investigation is to determine the temperature influence on the microstructure evolution and mechanical properties of the age-hardenable aluminium alloy using the developed technique.
The mechanical properties were as follows: tensile strength = 323 MPa; yield strength = 257 MPa; elongation = 6.3 %.
Microstructure and Properties.
Michailov, Comparative Analysis of Non-Uniformity of Mechanical Properties of Welded Joints of Al–Mg–Si Alloys During Friction Stir Welding and Laser Welding, Metal Science and Heat Treatment 60 (5-6) (2018) 393-398

Through analyzing Dabaoliang geological characteristics, this paper discussed the factors of the mechanism of landslide in Dabaoliang area and simulated its evolutionary process.
The heavy rain is one of the main factors caused the slope unstable and sliding.
Many factors could lead to the landslide body unstable.
The rainfall is one of the most important factors[1-3].
Due to its relatively poorer shale mechanical properties and weathering resistance, forming weak belt, soft interlayer, and even more sliding surface.

There has heretofore been a large number of research on the acicular ferrite steel [4, 5, 6], and the results show that compared with the traditional ferrite-pearlite steel, the acicular ferrite steel has better comprehensive mechanical property, and also has excellent welding performance and corrosion resistance.
Fatigue performance has become one of the most important performances of bridge steel for it directly affects the service life of the steel bridge.
In this paper, the fatigue limit and S-N curve of Q500q bridge steel were obtained by high-cycle fatigue test, the experimental steel fatigue properties have been studied through the fracture morphology observation and the analysis of fatigue crack initiation and propagation process.
The steel plates were produced using the thermo-mechanical control process (TMCP) that involves a controlled rolling and on-line accelerated cooling.
The crack tip stress intensity factor, K Ι , was calculated using the following equation [10]: Where σ is nominal stress, a is crack length and Y is form factor of the specimen.