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Compressive residual stress field and strain hardening effect induced by shot peening are well known two factors for an enhancement of fatigue behavior of structural components [1, 2, 3], but it seems hard to find a universal model that takes into account both factors and can predict, for example, residual stress relaxation during fatigue based upon changed mechanical properties in the peened layer.
Since most of components are thick enough as compared with shot peening affected layer, the yield limit of specimen in central zone will not be affected by shot peening, and residual stress in the region is near to zero.
Its conventional mechanical proprieties are listed in Table 1.
Mechanical properties of tested AISI304 stainless steel E(Young's Modules) [MPa] Yield Strength [MPa] Hardened Modules [MPa] 2×10 5 270 3200 Fig. 3(a) shows the initial distribution of residual stress measured using the hole drilling method.
With a comparison of the experimental and calculated results, it is anticipated that the region of surface in a depth less than 0.03mm will has different mechanical properties to the interior.

In this section, the models of surface generation are presented. 2.1 Modelling Surface Generation The modelling can be studied and investigated the surface generation in relation with the effects of machining process variables, tooling characteristics, and material properties which are directly affecting to surface quality.
As Cheng [5] has proposed, the inputs factors to the modelling approach are categorized in 4 aspects of sources which mainly include machine tools, cutting tools, operation conditions, and material properties, each source has 2 types namely linear inputs and nonlinear inputs.
All affected factors and the concept to create surface generation can be expressed as the flow chart in figure 2.
Figure 2: Linear and nonlinear input factors and modelling approach on the surface generation Although Cheung’s model was proposed the final mathematical model to generate the surfaces generation, it is quite a simple model by not concerning about the effects of factors affecting to the surface finish.
While Zhou taken into accounts the affected factors, but the processes of surface generation are quite complex and have taken many steps.

Probability theory determines how the uncertainties in crack size, loads, and material properties, when modelled accurately, affect the integrity of cracked structures.
The method can account for random loads, material properties, and crack geometry.
,X characterizing uncertainties in the load, crack geometry, and material properties.
The calculation of stress intensity factor affected by the randomness of crack size, elastic modulus and far field applied stress magnitude.
The load, crack size and material properties were treated as statistically independent random variables.

Test Results and Discussion Effect of CaCO3 Whisker Content on the Mechanical Properties of Cement Mortar.
The mechanical properties of mortar are shown in Table 3.
Effect of Fiber Content on the Mechanical Properties of Whisker-fiber-cement Mortar.
The effect of fiber content on the mechanical properties of whisker-cement mortar was studied.
Effect of Fiber Length on the Mechanical Properties of Whisker-fiber-cement Mortar.

It is necessary to study some basic parameters and factors such as bending stress, contact stress, frictional shearing stress and transmission error to indicate particular gear tooth contact properties [3].
Generally speaking, the researches regarding gear meshing are always focus on the meshing quality, gear tooth strength and relevant safety factors, fatigue, failure, noise and vibration, impact and so on.
The factors which should be considered adequately for eligible research modeling generation are perfect profile, good mesh quality and reasonable boundary conditions.
To acquire the most significant meshing properties responses, the coefficient of friction has been chosen as boundary condition variable due to its obvious nonlinear property, and the variable amounts will be defined as 0/0.1/0.2 in this paper.
The result of frictional stress can also reflect the frictional effects on other characteristic factors, and the particular frictional effects can be explained by the general situation of frictional stress.

The strain distribution and the max strain were affected by the diameter of laser spot.
Attainment of high draw ratio based on laser radiation heating might enable us to manufacture ultra-fine fibers even nano-scale fibers while the fibers could maintain excellent mechanical properties.
The fibers were tested on the DSC Q2000 (TA instruments) to measure temperatures and heat flows associated with thermal transitions and on DMA Q800 (TA instruments) to measure the mechanical properties as the increasing of tensile force in different temperature.
Figure 1 DSC curve of the sea-island fibers Figure 2 Effective stress versus true strain curves obtained as the increasing of tensile force at 25 ( ■), 100 ( ●) and 160 ( ▲) The mechanical properties of the PET/i-PP sea-island fibers in different temperature were shown in Figure 2.
The stress-strain curve in different temperature showed that the mechanical properties of fibers were sensitive for temperature.

It is found that springback is also sensitive to a range of material parameters, such as plastic anisotropy, evolution of elastic properties, yielding function and the Bauschinger effect particularly for loading/unloading operations.
Xu et al. [6] investigated the influence of some sensitive factors on the accuracy and efficiency of springback simulation.
Experimental Condition To characterize the material properties and anisotropy, different specimens from 25×100mm CK67 steel sheets were cut at different orientations to the rolling directions (0, 45, 90˚).
Tekiner, “An experimental study of the examination of springback of sheet metals with several thicknesses and properties in bending dies,” Journal of Materials Processing Technology, vol. 145, 2004, pp. 109-117
Feng, “Sensitive factors in springback simulation for sheet metal forming,” Journal of Materials Processing Technology, vol. 159, 2005, pp. 91-98

A double-ellipsoid heat source and the temperature-dependent thermo-physical properties of ZK60 magnesium alloy sheet are employed for performing a non-linear transient thermal analysis by a finite element method.
As a calculated result, the welding voltage, welding speed and the welding current are the main factors to determine the welding seam geometry.
The welding time will affect the heat transfer state during welding transient temperature field, special the ZK60 magnesium alloy has a high coefficient of heat conductivity.
It is same that the welding current is a decision factor during the LMF-GTAW process.
The project is also supported by State Key Lab of Mechanical Transmission, Chongqing University.

Cold rotary forging is an advanced but very complex incremental metal forming technology with multi-factors coupling interactive effects.
Although these researches have provided an important basis for understanding the cold rotary forging process, many problems are still not clear because cold rotary forging is a much complex metal forming process with multi-factors coupling interactive effects.
The workpiece material used in the model is AISI1020 and its mechanical properties are shown in Table 2.
It should be also pointed that the significant oscillation of force and power parameters will cause the variation of elastic deformation of cold rotary forging press, thus affecting the precision of cold rotary forged parts.
The results of this research show the following: (1) With increasing the distance L between the pivot point of the upper die and the centre point of the workpiece, the contact area between the upper die and workpiece becomes more uneven and the oscillation of force and power parameters becomes more significant, which will cause the more significant variation of elastic deformation of cold rotary forging press, thus affecting the precision of cold rotary forged parts

The microstructure was studied, mechanical and electrical properties were also analyzed.
Introduction In recent years Cu-Cr-Zr alloys have been widely used in electrical engineering due to their excellent conductivity and mechanical properties [1, 2].
The obtained mechanical properties of the alloy in various states are presented in Table 1.
As shown (Table 1, fig.4), aging of the UMFG alloy leads to a further improvement in mechanical properties.
Summary The effect of a combination of ECAP and classical rolling methods and aging on the microstructure, mechanical and electrical properties of the Cu-Cr-Zr alloy was studied.