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In order to search after their fatigue properties under cyclic loads, 33 specimens were tested, under different stress level and different stress ratio from each other, to observe their crack initiation lives and the failure lives, together with the growing short crack lengths at various cycles.
Many kinds of flaws, such as transitional round angles, cutting damages etc., which affect the fatigue life, may be regarded as notches.
Their chemical components were shown in Table 1, and the mechanical behavior after quenching and tempering treatment were shown in Table 2.
Table 1 Chemical components of the specimens (mass fractions w [%]) Steel C Si Mn Mo Cr P S 35CrMo 0.35 0.32 0.60 0.19 0.85 ― ― 42CrMo 0.45 0.28 0.63 0.19 0.90 0.016 0.01 Table 2 Mechanical properties of the two steels Steel Quenching Tempering Tensile strength σb[MPa] Yield strengh σs [MPa] Temperature t1[] Coolant Temperature t2[] Coolant 35CrMo 850 Oil 550 Water 1050 976 42CrMo 850 Oil 560 Water 1080 930 Steel Elongation δ[%] Reduction of area φ[%] Impact toughness Akv[J] Fracture toughness KIC[MPa.m0.5] Fatigue limit σ-1[MPa] Hardness [HSB] 35CrMo 14.5 57.5 63 ― ― ≥331 42CrMo 16.0 57.0 63 88 465 ≥300 The three-point-bend specimen was used in this study.
The stress concentrating factor Kt’ was determined by Neuber method.

The Design on Thermostatic Oil Tank of the Forming Equipment on Pressing and Spinning Ma Chun-sheng 1, a, Zhang Zhi-min2,b 1 College of Mechanical Engineering and Automatization North university of china, Taiyuan, Shanxi, China 2 College of Materials Science and Engineering North university of china, Taiyuan, Shanxi, China a sxtymcs@nuc.edu.cn, b rivermcs@163.com Keywords: The isothermal pressing and spinning, Thermostatic oil tank, Fuzzy--PID control.
But should also be considered to determine the thickness of three factors: First, it limits the quality required by the instrument; Second, if excessive heat, will form a thermal inertia, resulting in temperature measuring device unresponsive to temperature changes, temperature control circuit can be adjusted in a timely manner on the temperature, but affect the temperature accuracy; Third, if the wall is too thin, it can not withstand the force processing parts.
In the constant temperature layer shape, material certain circumstances, determine the temperature layer thickness d = r2-r1 becomes affected K value of the size of the key.
Temperature groove design and the heating resistance wire parameters calculated Thermostat bath at the top of the face seal performance of the thermostat bath temperature properties have an important impact.
China Mechanical Engineering.

Introduction Investigation on nano meter scale particles and development of fabrication methods for them have been executed widely and rapidly in the past a decade because of the drastic changes of optical [1, 2], electrical [3, 4] and biochemical [5, 6] properties comparing to those of coarse polycrystalline materials.
There are many methods for manufacturing the nano meter scale particles, which are mechanical grinding process, physical vapor condensation in air or in vacuum, and wet chemical process using oxidation and reduction reagents.
The rotation of substrate and the intermittent exposure of surface for the deposition source could significantly affect the initial nucleation mode and growth on the surface, as shown in figure 4.
Those parameters could also affect shape and crystalline of the nano particles, interaction between the nano particle and powder substrates, the composition of powder, which can be the important factors for understanding the effect of nano particles on medicine, mechanical lubrication, catalytic chemical reaction, quantum dot device, etc.

Sensing Unsteady Pressure on MAV Wings: A New Method for Turbulence Alleviation Matthew James Marino1,a*, Simon Watkins2,b, Roberto Sabatini3,c and Alessandro Gardi4 1,2,3,4 School of Aerospace, Mechanical and Manufacturing Engineering, RMIT University, Melbourne, VIC 3000, Australia amatthew.marino@rmit.edu.au, bsimon.watkins@rmit.edu.au, croberto.sabatini@rmit.edu.au Keywords: micro air vehicle (MAV), pressure sensing, turbulence, unsteady pressure, unmanned aerial systems (UAS) Abstract.
Under low atmospheric wind speeds (< ~ 5 m/s), turbulence is commonly created via thermal effects, whereas under higher wind speeds (~ 5 m/s), mechanical mixing dominates the turbulence generation mechanisms [4].
The calibration also takes into account the effects of surrounding environment and several other factors.
Wind Tunnel Test and Flow Properties All experiments were conducted in the “RMIT University Industrial Wind Tunnel”.
It was found that the partial tapping does not significantly affect the overall correlation between local and integrated Cp as the majority (approx. 76%) of the lift and pressure fluctuation occur within this area.

In 2005, a thermal-coupled FE modeling was conducted by Mitrofanov for VAC of nickel-chromium 718, which analyzed the effect on cutting force, cutting temperature and stress distribution with factors taken into account [7].
And in this paper, steel AISI 1045 is selected as the work piece material, which is the most representative steel with good mechanical properties and widely used in machinery manufacturing.
Too small depth of cut is not good for operation, which may cause abnormal cutting, and too small depth of cut will seriously affect the cutting efficiency.
As it is 3mm level of cutting depth, the amplitude should not be too large, or it will affect the stability of cutting.
Thermo mechanical finite element simulations of ultrasonically assisted turning [J].Computational Materials Since. 32(2005)463-471

Dynamic recrystallization It is important to determine the microstructure evolution during industrial hot rolling, which can predict the mechanical properties of the hot-rolled products, design the most effective hot rolling process to obtain the customer requirement, reduce the costs for routine operations and develop new products[12].Recrystallization is a process of fundamental importance in the thermo-mechanical processing of metals and alloys, which can result in grain refinement, reduce deformation resistance and directly affect the microstructures of the final product[13].
As a result, some mechanical properties, such as strength and impact transition temperature, can be improved.
Hence, it is necessary to understand such knowledge for prediction of mechanical properties and gauge control.Parameters εc express that dynamic recrystallization occurred critical deformation, it is a relationship between the value of the stress - strain curve εp that εc≈0.83εp.This test is the first under the stress - strain curve to determine εp, then find εc.
Mechanical Engineering[J], 2008.54 PP :219-224 Ning Yong-quan; Yao Ze-kun; Li Hui; Guo Hongzhen ;et al.
Mechanical Engineering[J], 2008.54 PP :219-224 [15] Ning Yong-quan; Yao Ze-kun; Li Hui; Guo Hongzhen ;et al.

In order to detect the arc plasma, an in-depth analysis on the relationship between the technology and film properties is conducted in this article.
As for the arc-discharge of new arc source, research on the plasma parameters is also required; otherwise, it can be judged only according to the arc or film properties, lack of essential analysis.
To measure properties of the plasma by using the probe is to analyze the relationship between current I flowing through the probe and the bias voltage U added to probe.
The above factors are considered in the design, and the fast recovery diode FR307 is selected.
Conclusions In order to detect the arc plasma, an in-depth analysis on the relationship between the technology and film properties is conducted in this article.

The influence of electro physical effects of varying intensity on the strength properties of the objects from powder materials, formed by 3D printing has been researched.
With the help of calculations according to this formula, we obtained the dependence of the efforts of the sample destruction on variable factors.
It happens due to the formation of the binder, which has dielectric properties of residual stress different from the basic material (powder) which leads to microcracking.
Summary The influence of electro physical effects of varying intensity on the strength properties of objects from powder materials, formed by 3D printing has been researched.
Dehoff, Thinking beyond Today: Comprehending the Potential of Additive Manufacturing Processes, Materials and Properties, Arlington, 2013

Effect of Lap Gap on the Frictional Performance of Shear-Type Friction Damper Pengbo Zhang 1,a，Zhixiang Yu 1,b, Yuping Sun 1, 2,c，Shichun Zhao 1, 3,d 1School of Civil Engineering, Southwest Jiaotong University, Chengdu, China 2 Graduate School of Engineering, Kobe University, Kobe, Japan 3 Key Laboratory of Seismic Engineering of Sichuan Province, Chengdu, China apengbozhang1226@yahoo.co.jp, b yuzhixiang@yahoo.com.cn, c sun@person.kobe-u.ac.jp, d swjuzsc@163.com Keywords: Friction damper, Hysteretic properties, Lap gap, Friction force, Friction coefficient Abstract.
These devices differ in their mechanical complexity and the materials used for the sliding surfaces [5].
Okada H. and Simizu K. [7], Sato H. and Hashimoto A. [8] studied the behavior of ordinary friction type high-strength bolted joints with gap, which shows that the slip load is affected by many factors such as lap gaps.
A formula was presented based on analytical models to evaluate the sliding load, taking many factors into account.

Leaching of the water soluble component was monitored and the results were consistent with the general correlation which predicts that binder removal time increases by a factor of 4 when the section thickness is doubled.
Particle size distribution and particle shape affect packing kinetics, debinding behaviour, shrinkage and final part density [5, 6].
Both particle shape and particle size affect mixing and subsequent moulding of the MIM feedstock [7, 8].
Wax improves flow properties of the feedstock during moulding.
Similarly the metal particles can affect the molecular bonding within the feedstock.