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In addition, the effect of the interfacial IMC on mechanical properties of solder joints was in-depth summarized.
It should be noted that the growth of IMC in interconnection solder joint is effected by many factors such as service environment, the size of solder joint, solder materials, service temperature and time.
The formation and growth of Kirkendall voids is decided by the following two factors, one is the growth rate of the interfacial IMC, the other is solubility of Cu into Sn and IMC under thermal aging [18].
Effect of interfacial IMC on the mechanical properties Strength of solder joints mainly depends on interfacial IMC [24].
In addition, when solder joints undergoing thermal and mechanical stresses, the dendritic Ag3Sn will seriously affect the mechanical properties of solder joints, and significantly decreases the strength of joints [26].

Using scanning electron microscopy, optical microscopy, hardness tester and tensile testing machine analyses the influence of double-fined treatment on microstructure and mechanical properties of GCr15 steels.
It depends on the in-depth understanding of the organizational structure, and the appropriate process measures.[5-8] The necessary condition to achieve superplastic are internal factors and external conditions.
The grain size is a important factor to affect the superplastic elongation size important factors.
The grain size is an important factor affecting the superplasticity.
The mechanical properties was evaluated using tensile tests.

Test combination design for the main control factors of the cement concrete strength was executed based on orthogonal test method.
The results show that the chiefly control parameter of affecting concrete strength is water cement ratio and the following are sand ratio and the coarse aggregate grading.
It can effectively distinguish the test factors, the primary and secondary function and trend of test index, and select the optimum combination of the optimum level of experimental factors and experimental factors[6].
The analysis reveals that the influence of water-cement ratio in three factors is the greatest to concrete compressive strength.
Binjing.Concrete technology (China Communications Publications, Beijing 1996) [6] Standard Test Methods for the mechanical properties of ordinary concrete (GB / T 50081-2002)

Aiming at the large amount of highly weathered soft rock along Shiyan-Tianshui superhighway, the physical and mechanical properties of the natural soft rock is analyzed.
Most of the studies focus on the mechanical properties and the construction characteristics of soft rock as filling material.
Physical properties and mechanical properties of the natural soft rock Composition analysis of minerals.
Comprehensively considering the economy and design factors etc, 5% cement should be mixed into the soft rock.
Experimental research on the softening of mechanical properties of saturated soft rocks and application [J].

The effect of nonstoichiometric Pb content on the properties of PZT has been studied.
However, the local structural grouping of the chemical composition exchange of the glass affects the amount of V"Pb in the crystal-grain layers and in this way influences the domain structure lability and its dielectric and piezoelectric properties [8].
The Pb2+ vacancies lead to the wall mobility and cause an observed increase in dielectric constant and loss, piezoelectric coefficients and coupling factors, and reduction in mechanical quality factor Qm and coercive field [9].
As reported, the dielectric properties will be badly affected by the PbO-rich amorphous intergranular layer (1-2 nm) [7].
Fig. 3 The dielectric constant of the samples with different Pb content as a function of temperature Table 1 Physical properties and dielectric properties of the specimens sintered at 1200 °C.

Mechanical properties and failure behavior of the spot welds in terms of peak load, failure energy and failure mode, were evaluated using tensile- shear test.
Relationship between welding current and mechanical properties was investigated.
It was found that the formation of brittle intermetallic compounds in the weld fusion zone is the key governing factor for mechanical properties of dissimilar Al alloy/low carbon steel resistance spot weld.
In addition, the formation of brittle intermetallic compounds at the weld zones deteriorates the mechanical properties of the joint.
Mechanical properties-As can be seen in Fig. 7, generally increasing welding current increases peak load and energy absorption.

Deformation of the geo-grid rein-forced retain fly ash wall and the reinforcing effect of geogrid reinforcement, depends largely on the role of interface properties between the geogrid and fly ash.
Interface in the numerical simulation of the mechanical properties of the main elements reflected in the geogrid on the constitutive parameters,for example, shear stiffness,Cohesion,Modulus, reinforcement length and so on.
Interface in the numerical simulation of the mechanical properties of the main elements reflected in the geogrid on the constitutive parameters,for example, shear stiffness,Cohesion,Modulus, reinforcement length and so on.
The elastic modulus of geogrid geogrid affecting geogrid reinforced retaining walls and reinforced fly ash an important factor in effect for the study of reinforcing effect on the elastic modulus and wall stability, Select 30e9pa, 50e9pa, 80e9pa elastic modulus of three different simulation.
Elastic solid mechanics.China railway publishine house.1990 [5] Wenxi Huang.Soil Engineering Properties.Beijing: China WaterPower Press.1993

The concrete that adds suitable amount of pozzolanic materials (ex. 10% slag + 10% fly ash) has the optimum microstructure and mechanical property.
Such that, adding slag and fly ash will change the microscopic properties of mortar at early and late ages.
The strength of concrete at early age mainly comes from the cement hydration, so the dominated factors are of W/B or the cement content.
All the interaction effects’ variances of factors are very small, it can be concluded that the main effect of slag or fly ash to the strength won’t be affected by the other mineral admixture.
As the age reaches 91 days, W/B still has the greatest influence, and the other factors have no significant influence.

In time past, designs of shafts were conservative in approach as relatively low working stresses were employed to cover up for unknown “Factors of Ignorance”. [1].
The factor so chosen is the factor of safety.
This range will be higher if there are only approximate values for shaft loadings, geometry and material properties or if there are grave consequences for shaft failure.
The factor of safety employed in the design of shafts depends on factors such as degree of safety required, materials used, purpose of shaft, accuracy of the values used in computing the loadings, geometry, mechanical properties etc.[3]
“Mechanical Engineering Design”, Fifth Edition.

This design method, where the various disciplines affecting the overall performance of the rock drill are separated artificially and optimized respectively, would obtain likely a local optimal solution substitute for the overall optimal solution.
In addition, that in this design there is little or no consideration of uncertainty factors affecting the overall performance of the machine, such as manufacturing technology, material properties, geometry, work load and environmental, or that the change of the design parameters and noise factors is too sensitive, makes the designed multi-functional cutting machine unreliable, or the adopted measure is too conservative to economic.
Its core content is uncertainty analysis that studies the influence of uncertainty factors changes on the product or system performance.
High Efficiency and Precision MROD Method With the different in the usage environment and requirements, the random distribution information affecting the design parameters of whole performance are different.
Du.: China Mechanical Engineering, Vol.17, No.17( 2006), p.1834-1841