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The combination of a hard, brittle outer layer and a compliant, tough inner layer offers high wear resistance and damage tolerance, factors that are crucial to the lifetime of such structures.
These studies have enabled the identification of various damage modes and the effect on stress fields of geometrical variables such as coating thickness, indenter radius and sample radius [1-5, 7, 8], as well as material properties such as interlayer elastic modulus.
Input material properties and geometries were chosen to mirror concurrent experimental work.
Dental composite (Tetric EvoCeram, Ivoclar Vivadent, USA) with a Young's modulus of 13 GPa and Poisson's ratio of 0.22 was chosen as the support material, as it closely matches the properties of human dentin.
The primary stress region under the soft indenter is close to the margin area, where the stress is affected by coating taper.

In [18] experimental and finite element tests on the material properties of a customized wrist orthosis produced with 3D printing were combined.
In this way the computational model provides with the possibility to assign different material properties to bones, joints and soft tissue, while accounting for the exact contact surface.
Literature models often treat the hand as an entire solid, assigning average mechanical properties and with linear elastic laws, not to overload the calculation burden because hyperelasticity can induce longer computational times [22,30].
The values of these material parameters were the same as in [32] and, following [31], the hand was assumed as a homogeneous body assigning the same properties to the remaining soft tissue volume.
In this way, different properties could be assigned to soft tissues and bones, but no contact interactions were needed at this internal interface.

This paper aims to find out the key risk factors existing in the oil pipeline as followed: corrosion, machinery and material failure, the third-party damage and maloperation.
Building the Fault Tree of Refined Oil Pipeline The fault tree of refined oil pipeline takes the pipeline failure as the top event, which is the main factor affecting the stability of the refined oil pipeline.
landslide 29 30 31 32 33 34 35 Pipeline material and design security system is unsatisfactory Wrong   rules and regulations Social relationship status safety equipment failure Operation personnel competence operating supervision 36 37 38 39 40 41 42 Lack of corresponding instruction Lack of elementary knowledge Lack of emergency exercise welding material quality maintenance management lack of training plan maintenance equipment 43 44 45 46 47 48 49 Lack of strict tests for mastery knowledge Maintenance personnel responsibility senses thickness of Anticorrosion insulation coating bond force of Insulating anticorrosive coating Fragility of Insulating anticorrosive coating breakage in Insulating anticorrosive coating Wrong position operating procedure 50 51 52 53 54 55 56 lack Pipeline safety education selection of welding methods Insulating anticorrosive coating aging pretreatment conditions of Welding surface Existing gas in welding surface Length of Not welding parts weak public moral property
awareness 57 58 59 60 61 62 63 anti-corrosive pipeline material is not up to standard filled soil contains corrosion material cleaning of welded surfaces Economic development along pipelines internal coating thickness diameter of filled soil particles filled soil water ratio 64 65 66 67 68 69 70 pipe trench drainability Existing crack on pipeline Pipe defect pipe joint electric current disturbance cathodic protection failure amount of bacteria in soil 71 72 73 74 75 76 77 The depth of pipe drain soil water content Soil sulfide content soil redox potential soil salinity mechanical damage corrosion detection 78 79 80 81 82 83 84 Remaining stress slope stability buffered etch failure cleaning efficiency process quality Construction supervision piping material Table 2 Intermediate Events in Fault Tree of Refined Oil Pipeline A B C D E F Third party activity corrosion cracking natural disaster Operational illegal construction stealing oil from borehole G H I J K L pipeline extrusion Stress
Corrosion operating misoperation maintenance misoperation construction misoperation legal factor M N O P Q R line-cruising agricultural activities public education exterior activities acid medium tensile stress S T U V W X the man-made misoperation construction defects special medium Corrosion staff training drainage construction anticorrosion and insulation layer Y Z A1 B1 C1 D1 pipeline welding pipeline installation corrosion internal corrosion external corrosion anticorrosion measures E1 F1 G1 H1 I1 J1 anticorrosion and insulation layer decreased initial imperfection anticorrosion and insulation layer decreased in operation existing defects unqualified pipes construction defect Fig 1 Fault Tree of Refined Oil Pipeline Fig 2 Continued Fig 1 The structure importance sequence of the fault tree Analysis of Fault Tree of Refined Oil Pipeline Basic understanding of the FTA.

Corrosion fatigue is an issue in military and commercial aircraft, affecting the structural integrity and useful life of an aero structure.
The differences of the FCGRs between the air and corrosive environments are seen to increase gradually, with a decrease of the stress intensity factor range.
The CFCP depends not only upon a mechanical driving force for the cracking, which is quantified by the stress intensity range (ΔK = Kmax–Kmin) and the maximum stress intensity (Kmax or R = Kmin/Kmax)[8], but also upon an environmental driving force[9].
The interaction between corrosion and fatigue reduces the cyclic threshold stress intensity factor range and increases the rate of crack propagation.
Summary Based on detailed mechanical testing and corresponding TEM analysis, we can make the following conclusions: (1) The corrosion environments used in this study have an obvious influence upon the fatigue crack growth rate.

Design and magnetic field simulation of Giant Magnetostrictive bone conduction pronunciation vibrator ZHAO Zheng-long*, HE Zhong-bo, LI Dong-wei, XUE Guang-ming, YANG Zhao-shu Department of Vehicles and Electrical Engineering ShiJiazhuang Mechanical Engineering College ShiJiazhuang, China 498836250@qq.com Keywords:Giant magnetostrictive; bow type structure; vibrator; simulation Abstract.
Giant magnetostrictive material (GMM) has the characteristics of big magneto-mechanical coupling coefficient, enormous strain and broad frequency response, which is widely used in audio and ultrasonic technology, ultra precision machining, testing technology, fluid control, vibration control and all kinds of sensors in recent years.
With the traditional magnetostrictive material and piezoelectric ceramics (PZT) compared to the GMM has the following advantages [5.6]: (1) The dependent variable is very big, in terms of the value of the magnetostrictive strain, it is better than pure Ni and piezoelectric materials 30 and 3 ~ 5 times greater respectively; (2) The output force that strain produces is very big, and the load capacity is strong which can reach 220 ~ 800N; (3) Electromechanical coupling factor K33=0.7 ~ 0.8, significantly higher than that of the piezoelectric ceramics and other materials; (4)The Change of the elastic modulus can be controlled due to the change of the magnetic field; (5) Response time is very short, only 10 ~ 6S; (6)The frequency characteristic is good, frequency band is wide, the ability converted into mechanical energy is better than any other material in the range of 0 ~ 5 KHz; (7) The stability characteristics are good with very high reliability, the magnetostrictive properties
Because of the stationary fixed surface, bending deformation of tapered bow structure on both sides is finally converted into the mechanical vibration of the output surface to the right along the graphic direction of the vibrator, realizing the audio signal transmission of bone conduction device.
The output surface, fixed surface and the bow structure are of the same material which is set to be the low magnetic or high magnetic materials respectively, but the output end and the fixed end does not belong to the vibrator magnet circuit so that the internal magnetic field of GMM rod will not be affected, therefore both of them will not be considered in the analysis.

A list of some of their properties is presented in Table 1.
As can be seen from Table 1, there are small differences between the two grades and their mechanical properties.
Specific material properties of GUR 1020 and 1050.
Sterilize the components in a manner typical of that in clinical use for such devices, including total dose and dose rate, as these may affect the wear properties of the materials.
As secondary factors that contributed to increased wear rate include positioning errors.

CTO like any other bio-based raw material has varying composition based on several factors, such as the type of the trees, geographical location, season of harvesting etc.
The physical and mechanical properties of the foams were measured in accordance with the following standards: foam density ISO 845, compression strength ISO 844, closed cell content ISO 4590, water absorption ISO 12087.
This peculiarity of the polymeric matrix influences the physical and mechanical properties of the obtained rigid PUR foams and especially it decreases the water absorption of these foams, which is important for material, so it would retain a high buoyancy for a long time [10].
Differences in closed cell content were affected by the chosen blowing agent: physical type or chemical type.
Vilsone, Characterization of polyurethane networks structure and properties based on rapeseed oil derived polyol, Eur.

We performed electrical deformation experiments on the film actuator under different prestrain ratios. 2.3 Material characterization 2.3.1 Mechanical property The mechanical properties were carried out with a tensile machine (Shimadzu corporation, AUTOGRAPH AG-X) using dumbbell specimen.
Table 1 shows the mechanical and electrical properties of them.
The properties are summarized in Table 2.
This may come from the fact that the increase of the dielectric constant is smaller than the increase of Young’s moludus and dielectric loss factor.
Properties of actuators for the matrix and composites containing BaTiO3 of different volume fraction.

Physical property of shrink-fit holder and cutter Fig.1 Structure of shrink-fit holder The material properties of SFH and cutter are in the table 1.
The material properties of SFH and cutter showed in table 1.
Kd is the distributional factor of curve’s slope of ε changed with the d.
Journal of Mechanical Strength. 31(1) (2009)88-94
China Mechanical Engineering. 14(9) (2004) 734-74

Modal Analysis of Stator and Rotor in Large Capacity Permanent Magnet Motor Shenbo Yu 1, a, Lei Li 1,b , Shen Cao 1,c 1School of Mechanical Engineering, Shenyang University of Technology, Shenyang, P.
These factors determine the modulus of elasticity of winding.
Property of each material can be determined.
Fig.2 Order 1 mode shape (lamination) Fig.1 Order 1 mode shape (entity) The winding affect model of large motor stator.
It means that natural frequencies of rotor are hardly affected by the magnets.