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Creep property of solder alloys is one of the important factors to effect the reliability of surface mount technology (SMT) soldered joints.
The Ref.[1,2] researched the relationship between creep properties, microstructure of SnAg, SnCu and SnAgCu lead-free soldered joints and its rupture lives.
It had been proved feasible and useful to add tiny rare earth (RE) in the lead-free solder to improve or increase the creep properties of soldered joints[4-7].
But there are very few reports about the study of creep properties and reliability of low Ag content SnAgCuRE soldered joints[8].
Results and discussion Creep properties of Sn2.5Ag0.7CuXRE lead-free soldered joints.

Vibration analysis based on the mathematical model of the air-suction device tillage seeder seeding Xu Zhanga, Manquan Zhaob , Fei Liuc, Shuai Dong, Yueqin Liu Mechanical and Electrical Engineering College of Inner Mongolia Agricultural University, Hohhot 010018 China aZhangxuzxy2013@sina.com, bnmgzmq@yahoo.com.cn.
cafei2208@163.com ＊Corresponding author: Manquan Zhao Keywords: Air-suction tillage planter; vibration characteristics; mathematical model ; seeding device Abstract: In order to study air-suction when tillage planter in the field farming, Vibration due to the surface roughness of the resulting excitation tillage effects on seed planter of the device, Derivation of the air-suction device tillage planter seeder vibration characteristics of the mathematical model, Vibration characteristics of the mathematical model derived gas suction device tillage seeder seed planter primarily by structural properties, Forward speed when operating, Seed row distance between the soil surface, Soil roughness and soil sticky decision.
Air-suction tillage planter by crop residues, stubble and soil affect irregularities in the work process, so that no-till seeder air-suction generating random vibration during operation, thereby affecting the reliability and seed planter box air suction Seed quality.
Effect of vibration by about two aspects of seed box: first, by learning the basic laws of dynamics and vibration or theorem [4], the establishment of air-suction vibration mathematical model tillage planter, planter can field vibration test influencing factors and provide the overall structure optimization tillage planter provide a theoretical basis; Second, by field vibration test, vibration spectrum analysis, research tillage planter seed box vibration characteristics.
Vibration mathematical model For secondary factor vibration characteristics and seeding performance of air-suction device tillage seeder seeding ignore the impact model to sit before the following assumptions: first, assuming that the individual components are rigid no-till planter.

In lapping, the velocity is one of the vital factors.
In the process of polishing, the properties of polisher material and abrasive powder are the essential conditions to ensure the super-smooth surface.
Experiment shows that the process parameters affecting surface roughness and lapping efficiency are abrasive properties and size, concentration of lapping slurry, lapping speed and lapping pressure, etc.
The lapping parameters (lapping speed and lapping pressure) affecting stock removal of KTP are changed, and the relations between stock removal and the parameters are in Fig.1 and 2.
(4) The properties of the polisher material and abrasive powders are essential conditions to ensure the super-smooth surfaces

In this paper, regardless of the cooling system of the mold, the optimization design for the material distribution of heterogeneous injection mold is investigated, which is made of two base materials with different thermo-mechanical properties.
Material Properties Description of Heterogeneous Mold Assume that the mold is composed of two constituent particles 1M and 2M with different material properties 1Mπ and 2Mπ .The overall properties at any point P inside the mold are determined by the linear rule of mixtures[1,2]: 1 2 1 2 1 2, 1 P M M f f f f π π Π = ⋅ + ⋅ + = (1) where 1f and 2f are the volume fractions of material 1M and 2M , respectively.
During the solidification process of casting, the uniformity of casting temperature distribution significantly affects the finished part quality.
Considering the von Mises stress constraints of the mold, the mathematical model of the material optimization of heterogeneous mold is formulated as follows: nix Ne eXe ts XFwXFw Minimize i me Nee ,,2,110 .,,2,1 ),(max.. )()( 0 22 11 L L =≤≤ =≤ ⋅+⋅ ∈ σ σ (5) where 1w and 2w are weight factors, respectively, Ne is the element number of the mold, 0σ is the inherent allowable stress of the mold, meσ is the von Mises stress of the e-th element of the mold.
The convection properties: h=1600W/m2℃, Ta=20℃. 0σ =830MPa.

Conventional methods for sintering and melting of titanium powder are costly, as they are energy intensive and require high vacuum, 10 -6 Torr or better, since titanium acts as a getter for oxygen at high temperature, adversely affecting mechanical properties.
For decades, titanium usage was only where critical to meet very high quality, tolerances, reliability, purity, structural integrity and other factors because of the high cost of the manufacturing process which was typically a vacuum arc re-melting (VAR) process.
Prior to beginning processing the chamber was pumped down to a pressure of about a millitorr using a mechanical pump followed by a sorption pump.
in the titanium powder compact limited the densification of the sintered material but did not affect the melted material provided it was held above the melting point long enough for the gas to escape.

The interest in studying nano sized particles lies in its ability to produce single phase BHF which could affect value of its crystal parameters as well as affecting its overall physical properties.
As we know, a lot of factors affect the characteristics of BHF such as synthesis method, the ratio of Ba2+ to Fe3+, as well as the molar ratio of citric acid to the metal nitrate, pH in starting solution, the annealed temperature, etc.
In this research, we investigated the influence of molar ratio Ba2+/Fe3+ on shifting of diffraction peak which absolutely affected lattice parameter as well as the overall magnetic properties.
The water solution was left to evaporate at 80oC with continous mechanical stirring until a sticky and foamy gel was obtained.
There are no traces of impurity phase α Fe2O3 and intermediate phase BaFe2O4 which are canted antiferromagnetic may contribute to the reduction of magnetic properties.

Introduction Emulsion polymerization process and formulation determine the particle structure, configuration and surface properties of emulsions, also decided the stability of emulsions [1].
The emulsion stability is also affected by many factors, such as electrolyte, mechanical action, freeze, melting effect and storage time etc.
The capacity of polymer emulsion to withstand damage by external factors is called stability of emulsion [2].
Therefore, for guidance of emulsion’s synthesis, storage and application, it has great significance to study the stability of emulsion properties and performances [3, 4].
Paper impregnated dry strength properties within a certain period of change is largely affected by its toughness and stiffness, after cross-linking emulsion relatively well connected, bursting strength is not the highest, followed by gradual flexibility, resulting in a corresponding increase in its resistance to breaking performance, stiffness performance gradually declined.

The structural, morphological and magnetic properties of the powders were investigated.
Another factor that affects the magnetic properties of the sample is a possible contamination of the sample with carbon from the mould and punches of the SPS equipment.
Alleg, S.Kartout, M.Ibrir, S.Azzaza, N.E.Fenineche, J.J.Sunol, Magnetic, structural and thermal properties of the Finemet-type powders prepared by mechanical alloying, J.
Eckert, Microstructure and magnetic properties of amorphous/nanocrystalline Co40Fe22Ta8B30 alloy produced by mechanical alloying, Mater.
Zhang, Structure and magnetic properties of bulk Fe56Co7Ni7Zr10B20 magnetic alloy fabricated by spark plasma sintering, J.

Formability enhancement Temperature, hydro forming and application of hydraulic counter pressure are some of the key factors that determine the formability of a material.
At high temperatures grain growth phenomenon takes place that adversely affects the mechanical properties and surface roughness of the product [2].
Experimental Procedure Punch diameter [mm] 62 (1:100 taper) Yield stress [MPa] 133 Punch profile radius [mm] 4 Ultimate tensile strength [MPa] 293 Die diameter [mm] 65.6 Strain hardening exponent 0.22 Die profile radius [mm] 6 Table 1 Dimensions of punch and die and properties of the sheet metal Figure 1 Tooling for warm deep drawing with hydraulic counter pressure.
The sheet metal is deep drawing steel (ASTM A591) and its properties are also mentioned in Table 1.
Hawkins: Journal of Mechanical Working Technology Vol. 11 (1985), p. 5-21 [4] H.

FBG embedded in the 3D braided composite materials has not more effect mechanical property of materials.
In the internal structure of FBG into measurement, fiber grating is due to the effect of matrix and the yarn around, the actual measurement results will be affected by many factors.
(2) Experimental results show that the 3D braided composite material under tensile load with the internal strain and FBG changes, have excellent sensing properties due to the FBG..
(3) Implanted fiber to the mechanical properties of composite, so less influence on 3D braided composites state health monitoring provides a good basis.
References: [1] Wan Zhenkai .Acoustic emission analysis of the flexural and tensile properties of 3D braided composite materials[J].Journal of Textile Research,2007,28(4):53-55