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The quality of bearing cages is influenced by a variety of technological factors which depend on the material they are manufactured of, on the hydraulic press and on the punching-stamping die.
On the other hand, roller bearings cages are usually made of materials with low hardness values and in such conditions, exploiting factors like external pressure and direct contact with other components can lead to damages like distortions or dents.
The proposed systemic approach of the stamping process shown in Fig. 2 will allow a easier identification of factors that may influence the quality and precision of stamped sheet metal cage windows, [5].
Results The results obtained by using the Cause & Effect matrix upon all the factors that are influencing the quality and precision characteristics as well as the analysis performed on the stamped sheet metal cages are shown in Table 1.
Processing properties 9 9 9 7 7 7 7 6 4 4 3 500 29.

Dynamic recovery does not occur at the early stage of deformation including the yield-point and the subsequent yield drop regime, but it is activated at a large deformation stage, where it is affected by both strain rate and strain.
Introduction Many high temperature mechanical tests of β titanium alloys show a common feature where the stress-strain curves exhibit a sharp initial peak stress followed by a constant flow stress or flow softening.
Hammond: Superplastic deformation properties of β-Ti alloys.
Cheng: Mechanical properties and deformation mechanisms of a commercially pure titanium .
Zaoui: Mechanical of Materials, Vol. 1: Elasticity and Plasticity ( Kluwer Academic Publishers, Netherland 1998). [16] G.

As a widely used Al-Mg-Si alloy sheets, the faster the quenching cooling rate leads to high supersaturation, which can be improved the bake-hardening properties of the alloy in the process of solution treatment.
However, when the alloy was isothermally-treated at medium temperature region (such as 350℃), the holding time seriously affected the supersaturation of the alloy, which ultimately affected the hardness after bake hardening treatment [7,21].
Residual stress reduction in 7175-T73, 6061-T6 and 2017A-T4 aluminium alloys using quench factor analysis, J.
Li, Influence of different solution methods on microstructure, precipitation behavior and mechanical properties of Al-Mg-Si alloy, Trans.
Effect of In addition on the precipitation behavior and mechanical property for Al-Mg-Si alloys, J.

Introduction Non-dispersible underwater concrete is described as tremie concrete, and is a new type concrete which can be poured underwater and whose aggregate and cement slurry separate in water is not like normal concrete. [1] In recent years, the construction of underwater projects is developing prosperously, concrete is still one of the most important and largest demand building materials in underwater engineering and the performance of underwater concrete will directly affect the quality of underwater engineering.
Because of the differences of mechanical property between non-dispersible underwater concrete and normalconcrete, it’s necessary to study the mechanical performance of columns.
The paper will use the experiment analysis way which study the mechanical performance of nomal concrete columns, discuss the mechanical performance features of non-dispersible underwater concrete columns with the experiment of axial compression and eccentric compression and provide a reference for researching non-dispersible underwater concrete.
Finally, taking all factors as a whole, we select secondary anti-washout admixture (UWB-II) which is manufactured by Engineering and Technology Institute of China National Petroleum in 2003.
Table 2: Mechanical property of concrete and longitudinal reinforcement Concrete Longitudinal reinforcement Material fcu(MPa) Ec(GPa) fy(MPa) fu(MPa) Es(GPa) NC 41 28 405 530 200 NDC 33 24 Specimens To better compare with normal concrete, the paper designs 3 groups, 6 concrete short columns (slenderness ratio is 4.5) on the basic of eccentric distance.

It was established that the fluence value affects the amount of magnetic α-phase.
Since the formation of this phase is connected not only with the change of the crystal lattice (fcc®bcc), but also changes in the magnetic, mechanical and corrosion properties, the study of g® α transition in irradiated steels is an important task of radiation material science and requires close attention [1].
Until recently the diffusionless g® αʹ transformation occurring in the process of cold strain of stainless steels was investigated using electron microscopy, X-ray analyzing, and identifying magnetic properties [6, 7].
This method is used to study a wide range of crystalline materials and, in particular, to determine the microtexture, crystallite orientation and properties of grain boundaries [8,9].
Fig. 6 also makes it possible to assume that the orientation of a grain is the factor which determines the form of the defect structure: whether blisters (101), or αʹ - phase (001) are formed. 

Research on the Shrinkage Cavity and Broken Graphite Mold Core of Copper Alloy in Horizontal Continuous Casting Sinian Li1, a, Yuan Chen1, b, Jiawang Ye 2, c, Shizhong Zhang2, d, Anchun Xiao1, e, Huimin Chen1, f, Zhong Zheng1, g, Hong Chen1, h 1 College of Mechanical Engineering, Hubei University of Technology, Wuhan, Hubei 430068, China 2 Wuhan Fanzhou Chuetsu Metal CO.LTD, Wuhan, Hubei 430015, China alisn@mail.hbut.edu.cn, b0710cy@163.com Keywords: Horizontal Continuous Casting, Copper Tube, Shrinkage Cavity, Shrinkage Rate.
Al element mainly solid solutes in the matrix and improves the mechanical properties of materials to meet the performance requirements of mechanical of synchronizer ring.
Summary From Fig. 4 and 5, it’s concluded that the solidus and liquidus temperature of FA6506 copper alloy are a little higher than FA6502 copper alloy, the productions are less affected by mushy solidification, so the quality of productions are better.
The content of Mn and Fe are the mainly factor.
(China 2003), p.18 [7] Shenghua Zhang, Xiangwei Zhao, Zhenzhen Zhan and Yinguo Xiao: Materials for Mechanical Engineering.

Although, commonly smaller cracks (<0.2mm) are considered as unproblematic and do not affect the strength properties of concrete, influence the material permeability and porosity based on the composition of the concrete [5].
The objective of this review study is to present in-depth information and comparison for the most recent types of bacteria that can affect on self-healing properties by enhancing their strength significantly.
Adding an inappropriate amount of precursor can negatively affect concrete properties, such as lowering final compressive strength [10].
Moreover, it founded out the positive and negative effects of microorganism on the mechanical properties of the concrete, particularly, compressive strength.
“Properties of Bacterial Rice Husk Ash Concrete.”

Introduction Due to the excellent thermo-mechanical properties, such as high strength, low irradiation swelling, low thermal expansion coefficient, and high thermal conductivity, Ferritic/martensitic (F/M) steels are generally considered as candidate structural materials for fourth-generation reactors and fusion reactors.
The presence of helium bubbles can affect the mechanical properties of materials, such as low-temperature irradiation embrittlement and non-hardening embrittlement at high temperatures.
Experimental results showed that high density of helium bubble can induced hardening to F/M steels [16], while the effect of He (size & pressure) on mechanical properties is still unsolved [17].
Properties of Helium bubbles in Fe and FeCr alloys.
Lucas, The evolution of mechanical property change in irradiated austenitic stainless steels, Journal of Nuclear Materials. 206(2-3) (1993) 287-305

The current limiting factor of this SHM strategy is the difficulty in differentiating changes between minor differences caused by small temperature changes and structural damage, and, compensation for environmental temperature variation is crucial [1].
Influence of temperature on GW propagation and compensation methods Elevated temperature can affect the transducers and their bonding, but this effect can be minimized via the choice of transducer types, materials and manufacturer[3].
Temperature change lead to changes in the geometrical and physical properties of the structure causing significant changes in the measured wave signals.
This time delay is proportional to the propagation distance, meaning that later parts of the signal will be more affected than earlier parts; this leads to an effect similar to a stretch of the signals in time.
Several related methods for correcting this time delay have been presented in the literature[1-6] based on time domain stretching of either the baseline signal or the current signal, estimation of delay as a function of time through local coherence and use of these values as factors for subsequent time-domain stretch, or simple frequency domain stretch.

The measured fatigue crack growth lives of structural steels are often affected by specimen thickness.
However, most of the studies were carried out under constant amplitude loading, and they did not consider the statistical properties of fatigue crack growth resistance and the effect of specimen thickness on the parameters of probability distribution for crack growth life.
It is, however, very difficult to determine separately these two random variables from the observed crack growth data even under the test for the condition of constant stress intensity factor range [12].
Since the present study is to investigate the effect of specimen thickness on inhomogeneity of fatigue crack growth resistance, it seems unnecessary to use the stochastic model considering the probabilistic properties of the parameters.
Using these properties, the random process S(x) is simulated.