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Thermo-mechanical reliability of the solder bumped flip chip packages having underfill encapsulant was evaluated with thermal shock testing.
The solder joints in a flip chip package serve as a mechanical mechanism for resisting the thermal deformation induced by the coefficient of thermal expansion (CTE) mismatch between the silicon die and substrate.
Therefore, this study was conducted to understand the thermo-mechanical behaviors of the flip chip package with Sn-3.0Ag-0.5Cu and a specific underfill encapsulation employing the thermal shock testing.
Some Cu6Sn5 particles were distributed within the solder, and this kinds of IMC particles were considered to be one of the influential factors controlling the mechanical properties and reliability of the solder.
This crack is not one shown in the case of solder joints without underfill, therefore, this crack formation should by affected by the thermo-mechanical properties of the underfill encapsulant.

The chemical and physical composition and mechanical properties of the hard slate of WCo8 grade are presented in Table 1.
Composition and physical and mechanical properties of hard alloy, grade WCo8.
[4] Zhixing Guo, Ji Xiong, Mei Yang, Cijin Jiang, WC–TiC–Ni cemented carbide with enhanced properties, J.
[6] V.S.Panov, Technology and properties of sintered hard alloys and their products, М., MISIS, Moscow, 2001
Zaytsev, Improved mechanical and tribological properties of metal-matrix composites dispersion-strengthened by nanoparticles, Materials. 3 (2010) 97–109

At the same time, the low content of carbon conducive to obtain uniform acicular ferrite and bainite structure during continuous cooling and improve the mechanical properties of steel.
The inclusions in the steel to is the root causes of the HIC, the formation of SCC are closely related to HIC, and important factor affecting the overall performance of the steel.
Pipeline steel future needs not only higher strength and toughness, but also with high deformation resistance and resistance to acid corrosion, stress corrosion properties, etc.
In the production of pipeline steel not only to control refining outside the furnace should be considered, also considering the comprehensive influence of rolling and other factors [27, 28, 29].
Materials factors influencing the initiation of near-neutral pH SCC on underground pipelines [A], 2000 International Pipeline Conference Volume 2 [C], ASME, 2000, 979 ~ 988

Application test shows that the polypropelyne(PP) products filled with inorganic modificated powder have superior physical properties or mechanical properties(tensile strength 20.45Mpa, bending strength 38.02Mpa) than that with uncoated wollastonite and pure PP and the heat distortion temperature increases by 28.6°C than pure PP.
Tensile properties test method Tensile properties were studied as per GB/ T1040-92.This test method has been used for the determination of the tensile properties of unreinforced and reinforced plastics in the form of standard dumbbell-shaped test specimens when tested under defined condi- tions of pretreatment, temperature, humidity and testing machine speed.
Flexural properties The flexural properties were studied as per GB/ T9341-2000.This test method covers the determination of flexural properties of unreinforced and reinforced plastics, including high-modulus composites in the form of rectangular bars molded directly.
,Ltd.The mechanical properties of PP filled by wollastonite before and after modification are shown in table 1.It can be seen from table 1 that the mechanical properties of PP filled by inorganic modificated wollastonite are evidently better than the one with wollastonite and the heat distortion temperature enhanced 28.6 than pure PP,which shows that inorganic modificated wollastonite has good effect on improving PP’mechanical properties.
Pan, Q.F.Yue, J.F.Ren:Polymer Testing.Vol.25(2006),p.384-391 [7] NIELSEN:Mechanical Properties of Polymers and Composites, 2nd, Marcel Dekker, inc, New York,1974 [8] B.

This report clarifies the effects of stress distribution and residual stress at the time of specimen preparation as influencing factors on the inelastic strain amplitude, which is a parameter in thermal fatigue life evaluation.
Table 1 shows the material properties used in the analysis.
In addition, since copper and solder are known to have different mechanical properties depending on the temperature [10, 11], a bilinear plasticity approximation considering temperature dependence was adopted (Fig. 3).
Table 1 Material properties for the analysis.
Schmitz, Mechanical properties of Pb-free SnAg solder joints Acta Materialia 59 (2011) 2731–2741

The thread rolling has many advantages compared to the machining process such as the low manufacturing cost, the high material utilization without chipping, the superior mechanical properties due to plastic forming, the low forming load due to incremental process and the high production speed [1].
Fig. 3 Thread rolling machine and dies for micro screw manufacturing Material properties.
Shear friction factor is set to 0.9 from the result of both literatures [4, 6, 7] and simulations.
The other shear friction factors make successive progression in the numerical simulation.
In practical manufacturing, the relative position between two dies is adjusted by experts during trial test since the position of a raw material is affected by various factors such as a small slip of a raw material according to the shear friction coefficient, high stroke speed of moving die, and misalignment of two dies in set up stage in micro sized parts forming process.

For CNTs, regardless of single-walled CNTs (SWNTs) or multi-walled CNTs (MWNTs), exhibit a great advantages in many fields, it has excellent elastic buckling property, good electrically conducting, and perfectly thermal properties [1].
Tab.1 the physical-chemical properties of CNTs OD or thickness Purity Length EC SSA CNTs dispersed 20nm >95% 0.5 mm >90 >350 CNTs film 20nm >90% 50 mm >90 >350 Method and experimental.
Under the action of the bonding head press the workpieces with ultra-high frequency vibration, the clinged bonding surface of different weldment would be melt and bond together immediately, so high weld strength, narrow heat affect zone and some other well mechanical properties welded joint was obtain.
What’s more, the frequency of ultrasonic vibration was another important factor affect the combination of CNTs and metal electrode.
Good mechanical contact between CNTs and metal could obtain.

The durability of such parts depends on the physical and mechanical properties of the material and microstructure.
The shape of graphite inclusion affects the operational properties of products.
The unfavorable factors of operation are the uneven operation’s mode (more intensive use in seasons without negative temperatures) and the fact that the machines are often operated in remote areas.
An important factor that affects the structure and properties of the diffusion layer is the possibility of oxidation for silicon and manganese base cast iron.
Krishtal, Structure and properties of alloys treated with laser radiation / M.

In order to improve the accuracy of simulation, the material is tested by the Gleeble-1500 thermo-mechanical tester to get the true stress-strain data, and then the VUMAT(User-defined Material Mechanical Behavior) programme is written to define material model.
Taking into account the limit of the computer memory and stress property, the mesh is denser in the contact zone between rollers and workpiece based on subdivision method by inserting new points in the model.
The deformation and deflection of roller is an important factor for affecting the accuracy of the shape and dimension of workpiece.
The mechanical property of flange can be decreased through increasing the flange reduction, but that of web be improved.
Chen: Chinese Mechanical Engineering vol. 18 (2007), p. 1747 (In Chinese) [2] Q.Q.

However, the micro-crack nucleation and the propagation of “dominant” crack are strongly effected by stress state, microstructure of material and environmental factors.
The characteristic mechanical properties obtained from standardized experiments of tensile specimens are given in Table1.
Table.1 Mechanical properties of low carbon steel Mechanical properties At 20 degrees Celsius At 400 degrees Celsius Yield strength (Mpa) Tensile strength (Mpa) Elongation (%) Elastic Modulus (Mpa) Poisson’s ratio 335.5 471.98 32 2.28×105 0.303 330.5 421.58 25.4 2.05×105 0.296 Fig.1 The metallographic micrograph of low carbon steel Fig. 2 Geometry of the notched specimen Testing techniques and optical observation.
With the reducing of notched radius or the increasing of nominal strain amplitude, crack growth rate increased relatively, which meant geometry and loading conditions were the factors of the crack propagation.
The geometry and load conditions affect the damage rate, which means the smaller the notched radius, the greater the slope of surface damage variable curves is, also the larger nominal strain amplitude, the greater the slope of surface damage variable curves is.