Search results

F is a scaling factor in the optimal range of 0.5 to 1.0.
The properties of the materials constituting the studied structure are presented in the Table.3.
Material properties.
Material properties SAC305 FR4 resin EPOXY copper Young's modulus (GPa) 51.3 17 17 115 Poisson’s coefficient (without) 0.35 0.39 0.24 0.31 Density (Kg/m3) 7400 1800 1800 8890 Coefficient of thermal expansion (mm/K) 20 18 22 17 Shear modulus (GPa) 19 2.4 7.4 44 The temperature cycle applied to the structure is of a duration of 60 min.
Tan, Development of convective reflow- projection moiré warpage measurement system and prediction of solder bump reliability on board assemblies affected by warpage.

The material properties of magnesium alloys [1] Although pure magnesium has many advantages, but has lower mechanical properties, it has great restricted.
By the alloying elements in pure magnesium, it can significantly improve the physical, chemical and mechanical properties.
Magnesium alloy’s linear expansion coefficient, cutting heat, temperature and other factors will affect the accuracy of magnesium alloy parts, in choosing allowance, tool geometry, cutting parameters and fixture design, detection method, we have to make a good measure.
Most of forging magnesium alloy material use extrusion blanks, it was dealt with homogenization treatment before squeeze, reducing the anisotropy of mechanical properties.
Rapid solidification technology [5] Rapid solidification technology is a molding process emerging in recent years, the use of this technology can get very small grains, thereby enhancing the mechanical properties of alloy and thermal stability.

Due to the polymeric nature of adhesives, the variation of the mechanical properties of the adhesives with temperature is one of the most important factors to consider when designing a bonded joint.
However, the properties of adhesives over the range of service temperatures need to be studied for each type of application.
Below Tg it is difficult to say at which temperature the lap shear strength is the highest as there are two factors to consider: the ductility and the strength.
Banea, L.F.M. da Silva, The effect of temperature on the mechanical properties of adhesives for the automotive industry, Proc.
Adams, Measurement of the mechanical properties of structural adhesives in tension and shear over a wide range of temperatures, Journal of Adhesion Science and Technology, 19 (2005) 109-141

Engineering practice shows that initial geostress field is one of the most important controlling factors which affect the mechanical properties of rock [1, 2].
Most of them think that the major factors affecting the distribution of geostress field in river valleys are gravity stress and tectonic stress, but the action of river valley erosion is less considered.
Inversion Method of initial geostress field in river valleys The basic idea of inversion.The basic idea of inversion for the 3-D initial geostress field can be shown as follows: a) A 3-D geological model is established according to geological conditions. b) Take the factors that may affect initial geostress field as undetermined ones, and obtain geostress values of measuring points under individual effect of factors by numerical simulation.
Influential factors and boundary constraints of initial geostress field.
Considering the factor of erosion affecting geostress field, we suppose that the surface is relatively flat in the early stage of the river valley.

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.

The improvement of these properties are related to close and homogeneous association of reactive powders and to the decrease of specific surface area favoring the powders hydration process enhancing setting reaction rate.
Fast-setting calcium phosphate cements for bone reconstruction are good candidates due to their excellent biocompatibility and bioactivity properties and their ease of use as mouldable and injectable self-setting pastes [1].
Several groups have explored the possibility to improve cement paste cohesiveness during injection using the rheological properties of natural and synthetic polymer additives [4-5].
Another approach consists in controlling reactive powders particle size and particle size distribution which are determining factors affecting paste cohesiveness, hydration process and mechanical properties of cements [2, 6-7].
Recently, calcium carbonate-calcium phosphate mixed (CaCO3-CaP) cements have been presented as promising resorbable bone cements [8] and the rheological properties of these original cement compositions are just beginning to be explored.

Effects on the Properties of Polyethylene Film Aging by Different Methods Chen Li1,2, ShengLing Xiao 1,2 a 1Northeast Forestry University, Harbin, 150040, China 2Key Laboratory of Forest Sustainable Management and Micro-bioengineering in Heilongjiang Province, Harbin, 150040, China aCorresponding author: shenglingxiao@163.com Keywords: PE film, ultraviolet aging, thermal aging Abstract.
Plastics expose in natural, and their properties are affected by light, heat, oxygen, water and other factors, the surface will appear yellow or crack, the performances are deteriorative and the use life becomes shorten.
Although at the beginning the cross-linking reaction has advantage, but then the cleavage reaction is dominant, finally, the polymer molecular weights reduce so that the mechanical properties decrease[3]. 3.
The results demonstrated that the effect on the air permeability of PE film by ultraviolet aging was higher than thermal aging, aging made the barrier properties dropped down, and the air permeability increased.
Ageing effect on the properties of tri-layer polyethylene film used as greenhouse roof.

While it has been established that CT improves the wear properties in some steels, the mechanism of this behavioral aspect is not yet fully known.
Most work has been focused on AISI M2 high speed steel related to the effect on different properties, but the microstructural change is not yet conclusively identified.
The factors affecting wear resistance of the high speed steels are related to microstructure [1, 2].
[5] A.Molinari, M.Pellizzari, S.Gialanella, G.Straffelini, K.H.Stiasney, Effect of deep cryogenic treatment on the Mechanical properties of tool steels, Journal of Material Processing Technology 118 (2001) 350-355
[6] V.Leskovsek, B.Ule, Influence of Deep Cryogenic Treatment on Microstructure, Mechanical Properties and Dimensional Changes of Vacuum Heat-Treated High speed Steel, Heat Treatment of Metals, 2002.3 pp. 72-76

The influences of each factor is discussed, and preventive measures are also put forward.
The main degradation pathways in oil recovery applications are chemical, mechanical, and biological[1].
Hydrolysis was significantly affected by temperature.
Both of them affect HPAM stability.
Polymer solution properties and displacement mechanisms.

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.