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One of the common methods used to improve the characteristic and properties of the lead-free solder is by the addition of another alloying element.
These issues had led towards extensive researches to develop suitable lead-free solders that have outstanding properties with great soldering performances same as Sn-Pb solders.
Among the important considerations for developing new lead-free solder are good wetting properties, good physical and chemical characteristics (e.g., composition, additives, melting temperatures, flux chemistry), mechanical metallurgical, fatigue resistant properties[9,10], manufacturing, reliability and costs [3].
Found that, addition of small amount of Bi to certain lead-free solder alloy compositions was to improve the wetting wettability and spreading properties and reduce the melting temperatures, as well as enhance the mechanical properties of the solder joints.
Zhao et al. [5] observed the influence of Bi on microstructures evolution and mechanical properties in Sn-Ag-Cu lead-free solder.

In this paper micro-hole machining is regarded as the research object, effects of many factors such as power supply natures, electrolyte composition, pulse width and pulse frequency on machining accuracy in micro-hole ECM have been evaluated.
Various types of micro-structures such micro-shafts, micro-holes, micro-slots, micro-gears，micro-paddles and micro-motors are used in communication systems and micro-electro-mechanical systems (MEMS) widely[1,2].
Experimental research of ECM for Meso-scale micro-hole is mainly introduced in this paper, the technological factors which influence ECM accuracy of micro-hole are scrutinized and studied, which mainly include power supply natures, electrolyte composition, pulse width and pulse frequency.
Effects of Power properties on machining accuracy of micro-hole Effects of machining voltage on side gap(single gap) distribution of micro-hole when using DC electrochemical machining is studied firstly.
Mechanical Science and Technology, 25(2) (2006)242-245

Geometric characteristics of reinforcing particles Reinforcement 6061 [Al] Average radius [µm] Average particle area [µm2] Aspect ratio Blocky Al2O3 (Mean value) 5.82 156.81 1.021 Standard deviation 5.30 289.3 0.0434 The main concern of the work is to study the properties and behavior of dissimilar friction welds with and without the presence of silver interlayer.
In this case the particle diameter d is related to measure width w, by a factor 4/π refer to the below given equation.
Main advantage is the friction pressure doesn’t affect the volume fraction of particles.
[7] a) Dunkerton, S.B., 1982, report 201/1982,“The effect of interlayers on dissimilar friction weld properties”, TWI, Abington Hall, Cambridge.
b)Dunkerton, S.B., 1982, report 229/1982,“The effect of interlayers on dissimilar friction welds properties” TWI, Abington Hall, Cambridge

Temperature Influence on the Viscoelastic Electromechanical Deformation of Dielectric Elastomer Jun-Jie SHENG1, a, Yu-Qing ZHANG1, b, Shu-Yong LI1, c, Hua-Ling CHEN2,d 1Institute of Systems Engineering, China Academy of Engineering Physics, Mianyang 621900, People’s Republic of China 2School of Mechanical Engineering, State Key Laboratory for Strength and Vibration of Mechanical Structures, Xi’an Jiaotong University, Xi’an 710049, People’s Republic of China ascu2005sjj@163.com, b412zhangyq@caep.cn, c412lisy@caep.cn, dhlchen@mail.xjtu.edu.cn Keywords: Dielectric Elastomer, Temperature, Viscoelasticity, Electromechanical.
Temperature can significantly affect the performance of a viscoelastic dielectric elastomer (DE).
DE exhibits time-dependent property and the deformation of DE is also highly relying on the rates of activation [7,8].
Recently, the influence of both temperature and deformation on dielectric constant is considered during the establishment of free energy function of DEs [19,20], but does not involve any viscoelasticity and no attempt has been made to describe how temperature affects the viscoelastic processes.
As the Maxwell stress drives the DE system substantially, thus the amplitude increases at the same time with the increase of the actuation factor at high temperature for the viscoelastic electromechanical performance of DE.

These structural parameters have mainly positive influence on important mechanical properties of superalloys.
Solid solution provides fundamental strength characteristics of superalloys (tensile strength, fatigue properties, creep resistance, and hot-corrosion resistance) [6].
Unique properties of superalloys are close related to fraction of γ'-phase.
For example, coarse γ'-phase means decreasing of mechanical properties due to easier slip of dislocations.
Metallography is a powerful tool at fatigue failure mechanism description and provides information how microstructure is related to mechanical properties.

Numerical Simulation of Sheet Metal without Burr in the process of Blanking Based on DEFORM for Manufacturing Engineering ShuTian Fan1, a, Yong Wu1, b 1 School of Mechanical Engineering, Jiangsu University, China astfan@ujs.edu.cn, bwywxnjzj@163.com Key words: Blanking;Burr-free; Numerical Simulation;Clearance Abstract.
No matter which kind of blanking process is adopted, even if we improve the strength and thickness of material, the clearance and other factors, the burr can be only limited to a certain height, and we still unable to avoid the generation of burr.
And it has a relationship with the thickness and properties of material, perimeter of blanking pieces, sharp degree of blade, punch-die clearance and other factors.
It shows that the blanking force is not significantly affected by the gap under normal circumstances.
It is illustrated that the clearance has little effect on blanking force under normal circumstances. 3) The quality of blanking is affected by the length of shear zone, with the increase of clearance, the length of shear zone presents the tendency of decrease.

The effective mechanical properties of the chopped strand mat (CSM) reinforced composite cylinder were recorded from the experiment which has modulus of Elasticity 197.707 N/mm2, Poisson’s ratio of 0.22 and density of 1250 Kg/m3.
Table 1 shows the mechanical properties of the chopped strand mats.
The bulk properties determination requires tension, compression and shear tests [27].
For fiber-reinforced polymers like the ones used in this study, their properties are those achieved from tensile testing.
Table 2 presents the physical properties of chopped strand mat thin-walled composite cylinder.

High temperature mechanical properties of due to improving significantly longitudinal plasticity, creep strength, creep rupture life and thermal fatigue property of superalloy [3-4].
High temperature gradient can increase the cooling rate during directional solidification, which refine solidification structure, decrease composition segregation and improve high temperature mechanical properties of casts [5-8].
The mechanical properties of superalloy with different structure scales, which were obtained under directional solidification with different thermal gradient, were investigated by many domestic and foreign scholars.
The effect of temperature gradient on the mechanical properties of superalloy can’t be completely reflected because of the lower solidification rate for the previous researches.
The mechanical properties of directionally solidified superalloy are affected by the dendrite arm spacing, γ' precipitate, micro-segregation as well as the crystallographic orientation.

Structure and Properties of Zinc Oxide Nanoparticles (ZnO-NPs). 1.1.
For example, top-down techniques can seriously destroy the crystalline nanomaterial’s structure, directly affecting their optical-chemical properties [33].
By optimising these factors, it becomes possible to control the shape of ZnO nanomaterials.
It is recognised that various factors related to leaf extract conditions, such as phytochemical type, metal salt concentration, pH, and temperature, affect the rate of formation of nanoparticles, their yield, and their stability [103-105].
Jafari, Evaluation of different factors affecting antimicrobial properties of chitosan, International Journal of Biological Macromolecules, 85 (2016), 467-475

As their inherent properties, the surface modification of such powders is as much important a factor which affects the quality of the powders.
In such a process, it is necessary and important to choose the proper coupling agent according to the inherent surface properties of the powders used, on which researches have received much attention in home and abroad.
It has been proved by X.Dong that the mechanical properties of the composite system filled with modified superfine saponite powders increase to a certain degree [2].
C.X.Xiong pointed out in their study of using superfine Al2O3 powders as flexibilizer and reinforcer for polyethylene that modification of the surface and prevention from agglomeration helped improve effectively the mechanical properties of the polymer system [3].
The change of surface properties indicates the change of groups on the powder surface, which can be proved by IR spectrum.