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The rate of loading is a main sensitive parameter that affects both damage initiation and propagation, as they increased significantly with increasing loading rate.
Introduction Real life structural materials are exposed to different types of loadings leading to material deterioration and change in their structural/mechanical properties.
This progressive physical process of degradation in the mechanical properties with complete loss of stress carrying capacity is commonly referred to as damage.
Mechanical properties were obtained from the uniaxial tensile tests of steel, as shown in Fig. 2, and the hardening behavior was mimicked using Johnson cook model (See Eq. 3).
Results are compared and discussed in terms of the effect of loading rate on the damage level Fig. 4 Views of the neck section with contours showing equivalent plastic strain and mises stresses Effect of Strain Rate on Damage Briefly, the deformation of materials under load depends on factors, such as atomic structure, rate of loading, and temperature.

However their mechanical properties and tribological properties are still lower than that of commonly applied materials.
Mechanical properties were evaluated by birnell hardness test in stir zone.
Tensile mechanical properties and failure behavior of FSP modified Mg-Al-Zn and dual phase Mg-Li-Al-Zn Alloys.
Microstructural and Mechanical properties of Al-Fe in situ Nano composite produced by friction stir processing.
Microstructure and mechanical properties of friction stir welded joints of AC4A cast aluminium alloy.

On the Firing Test Properties of Thinfilm Metallic Initiators Jenq-Huey Shuy 1, a , I-Tsung Lai 1,b , Ta Chang1,c, Yun-Cheng Wang1,d , Yan-Chn Wu1,e , and, Hao-Yi Lu1,f 1 Institute of Mechanical and Electrical Engineering, National Taipei University of Technology, 1,Sec. 3, Chung-Hsiao E.
The aim of this study was to investigate the firing test properties of NiCr alloy thin film bridge electro-initiators(detonators).
The purpose of the test is to explore how the process parameters of the thin film bridge detonator such as bridge shape, resistance etc. influence the firing properties of the electro-detonators and verify the firing properties with the firing test equipments.
Therefore, it is concluded that the bridge is the dominant factor influencing firing time.The different bridge connector shape in this sample group indicates the contact type between the two polars of the thin film bridge and the detonator GMS (pin and ring), and this factor does not affect the bridge width, thickness and length unless ectopic migration occurs in the bridge plating; in addition, it l w Substrate Thin film bridge Pin Ring should be noted that in the article the bridge area indicates the bridge shape area, the area of length x width, with the actual heating area ,which is relevant to the bridge thickness, being the total of the six side cross-sectional areas, and this applies to the next groups unless otherwise specified.
Fig.7 Function time vs. resistance Fig.8 The picture of GMS firing test Conclusion The research preliminarily verifies that the detonator (1.1～1.4Ω) firing time is about 180～200μs and that the shortest firing time is 120μs (3.165Ω).After the comparative study of the test, the factor influencing "firing function time" may be verified and deduced, and besides the "electronic heat power effect" and "resistance", it is also found and verified in the test that "bridge area" is the dominant factor influencing "firing function time" with the far greater influence than the "resistance" factor because of the "surface area heat dissipation effect" of the thin film.

Optional secondary processing often follows to obtain special properties or enhanced precision [1- 6].
The most important factor is the porosity.
Porosity changes the properties of thermal conductivity and harden-ability of the material and affects the welding process and affects its character because of the oxides and impurities within the structure.
Other important point is the design factors.
Sarıtaş, AU Isparta: J. of Mechanical Engineering, vol. 7, (1993), p.1 [4] R.M.

The brittle fracture was caused by structural factors.
The brittle fracture was caused by structural factors.
The actual fracture appearance is not only affected by materials toughness, but also structural factors and impact velocity.
The brittle fracture was caused by structural factors.
The brittle fracture was caused by structural factors.

Finally, considering the shale gas development in China as an example, the structural integrity (casing deformation) and seal integrity (Sustained Casing/Annulus pressure, SCP/SAP) were analyzed by clarifying the failure mechanism from the view of well integrity issues affecting shale gas production.
Finally, considering the shale gas development of China as an example, the failure mechanism of structural integrity (casing deformation) and seal integrity (Sustained Casing/Annulus pressure, SCP/SAP) and their influences on the single shale gas well production are analyzed from the perspective of the well integrity failure affecting shale gas production.
(2) Engineering Aspects The shale gas well casing deformation may occur at any stage of the gas well entire life cycle and is not caused by a single factor in a single stage but is a coupling result of multi-stage multi-factor.
The factors affecting the seal integrity of cement ring include [9]: (1) geological factors: leakage causes poor interface cementation and cement stone strength decline in high temperature; (2) drilling factors: well geometry and poor drilling fluid performance, low displacement efficiency, poor cementing quality, etc.; (3) cementing factors: poor cement slurry performance, mechanical properties of cement stone do not meet long-term sealing requirements; (4) development factors: many factors including fracturing, workover and adjustment lead to Impact Analysis of Failure Mechanism.
If not taken seriously, it will affect subsequent construction, and increase costs, and even affect safety production in the long run, resulting in inevitable economic losses.

The characteristics of the lasergenerated ultrasonic waves depend on a number of factors including the optical penetration depth, thermal diffusion and the elastic and geometrical features of the materials, and also on the parameters of the exciting laser pulse including the shape, focus spot and pulse width [1,2].
Further, it is essential that the heat-affected zone due to the deposition of laser energy be much smaller than the domain of mechanical waves [6].
The thermal and mechanical properties for the first and second layer of skin model used are Poisson's ratio of 0.499, Young's modulus of 88 kPa and 1 kPa, thermal expansion coefficient of 3.0x10 -4 K -1 and 9.2x10 -4 K -1 respectively [8].
The character of the surface wave dispersion is determined by the properties of the two layers in the model.
Analysis of these waveforms by calculating the phase velocity dispersion relations would allow an inverse solution to calculate material thickness and properties.

A heat flow model needs to be considered for the factors mainly variable thermal properties, temperatures of phase transformation, the magnitude of heat and characteristics of heat distribution, plate geometry, convection and surface depression in the weld pool [7].
Many researchers consider constant thermo mechanical properties to find out temperature distribution on welded plates.
The mechanical properties of the joints and value of ferrite share test have been done.
Analysis of welding heat input influence on mechanical properties of test joints has been done using heat input from 2.5 to 4.0 kJ/mm.
Experimental Methods The experiments were conducted as per the design matrix randomly to avoid errors due to noise factors.

In the shape detecting process, affected by temperature, humidity, magnetic field, vibration, installation geometric errors, process allocation and other working condition factors on site, online shape signals may be distorted in most case, and can not reflect true shape condition.
The differential circuits are composed of radial symmetrical two sensors for eliminating signal drifting which may be caused by temperature, humidity, vibration, magnetic and other factors.
The optimized structure of detecting roller not only has good mechanical transfer properties, but also has the maximum Mises stress in the safe range.
Multiple isolation measures were used to prevent industrial interference signals of magnetic, temperature, humidity, vibration and other external factors.
Journal of Mechanical Engineering, Vol. 47 (2011) No.12, p.56-61.

These properties make HSS more difficult to grind than other steels, especially when using conventional aluminium-oxide wheels.
The fatigue properties of punching tools are determined not only by the HSS material properties (e.g. carbide and inclusion contents, phase transformations) [1] but also by the thermophysical properties of the grinding process (undeformed chip thickness, wheel topography, energy partition, etc.), which affect the grinding temperatures.
For thermal analysis of grinding, it is of major importance to understand the factors which affect the grinding temperatures.
Specific grinding energy depends on numerous factors, such as sharpness of the grinding wheel, the grindability of the workpiece material, undeformed chip thickness, cooling-lubrication, etc.
The generation of tensile residual stress is strongly dependant on workpiece properties, in particular material yield stress.