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Wellbore integrity failure may be a result of one or more factors.
Irregularity hole sizes is one of complex situation caused by sidewall destabilization, it has many reasons, such as natural factors and human factors.
From the mechanical perspective, the main reasons of overcut and hole collapse is the lower effective fluid column pressure, which resulting in shear failure, due to the stress suffered by the rock of sidewall exceed the strength of the rock; From the chemical perspective, sidewall destabilization is mainly related to the matching of formation properties and drilling fluid system.
Aims at carried out a comprehensive and integrated management to all the factors affecting the well integrity in the whole process.
New Method for Determining Downhole Properties that Affect Gas Migration and Annular Sealing.

The hysteresis of viscoelastic properties of tire structure was shown the largest factor of the power consumption rate in the tire, the rough estimation of 90% of the total energy loss.
The final results and characteristic of the tire numerical modeling were depended on various factors which were the material data to yield the significant impact on the correction of the numerical results; therefore, an accurate characterization and validation on the tire rubber mechanical properties were required in the FEA of tires.
Specimen Preparation In order to prepare the specimens regarding to the standard test methods for mechanical properties of material which are ASTM D575 and ASTM D412, the TWEEL tire is cut using a water jet cutting technique as shown in Fig. 1.
Mechanical Properties Testing The prepared specimens were carried out to test in tension and compression using universal testing machine, Instron 5969.
Malachowski, Assessment of mechanical properties of offroad vehicle tire: coupon testing and FE model development, Acta Mechanica Et Automata. 6 (2012) 17-22

Introduction The manufacturing process of an implantable medical device, as an orthopedic implant that replaces a body joint requires mechanical safety and biocompatibility.
To safeguard the integrity of the device, as well as the tissues and organ adjacent to it, thus ensuring a better quality of life for patients, it is necessary that the mechanical properties do not change over their lifetime, or at least remain stable during an extended period of use.
Wear-induced failure remains a major limiting factor affecting the long-term performance of the joint replacements, particularly for younger and more active patients.
Recognition of the wear issue has led to extensive wear studies to predict wear performance, understand wear mechanism and evaluate design factors [9–12].
The surface finish characteristics influence several factors related to the properties of the biomaterials, among them the hardness, the wear, the friction [13] and the resistance to corrosion [14].

Prolonged stirring also improved the surface quality as the properties are improved.
From analysis, it is understandable that two factors are more pointedly causative to the surface finish viz. cutting depth and feed (37% and 38% respectively).
S/N charts (response wise) are used to identify the situations under which enhanced properties can be achieved for a particular single objective in consideration.
Mahapatra, Recent progress in aluminum metal matrix composites: A review on processing, mechanical and wear properties, Journal of Manufacturing Processes 59 (2020) 131-152
Ponshanmugakumar, An investigation on wear properties of SiC/WC strengthened aluminium alloy hybrid composites.

China 3 Department of Mechanical Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan ahub1616@163.com, bgoraka@chiba-u.jp, cninghuiming@chiba-u.jp, dhuning@faculty.chiba-u.jp Keywords: Piezoelectric property, Multi-walled carbon nanotube, Nanocomposite, Poly (vinylidene fluoride) Abstract.
However, on account of their low electromechanical coupling factor and relatively low generated voltage or force, the potential of piezoelectric sensor/actuator applications utilizing PVDF is still limited.
It is well-known that carbon nanotubes (CNTs) possess a unique atomic structure which leads to their excellent mechanical, thermal and electrical properties [4].
Many studies indicated that even a little addition of CNTs in polymer matrix may lead to remarkable improvements in its physical and chemical properties.
Then, the piezoelectric property of this nanocomposite film, which was affected by the MWCNT addition and the drawing and poling processes, were studied through a series of vibration tests.

The microstructure and physical and mechanical properties of the composites were examined. 1.
Physical and mechanical properties of the composite-building materials (at room temperature) assumed in the numerical calculations of the residual stress state [3,4,5].
The microstructure, physical properties (density), and mechanical properties (bending strength, microhardness) were examined. 2.
SUMMARY AND CONCLUSIONS The results of the calculations and examinations of the composites do not permit us to draw unequivocal conclusions whether the residual stress state affects the properties of the composites.
The properties of the composites seem to depend chiefly on the properties of the ceramic phase and its volumetric share.

Introduction Extensive applications of cemented carbides are due to their excellent mechanical properties, such as high hardness, high resistance, and good strength [1].
Grinding is the main method to machine cemented carbides at present, and the grinding characteristics of ultrafine-grained cemented carbides maybe change to some extent with the increasing of hardness, strength and other mechanical properties.
The material removal mechanism of ultrafine-grained cemented carbides in grinding process was studied [6], and it related to material properties.
Liu Lianbin and Zhang Bi et. al. [7] studied the material removal mechanism by grinding of nanostructured ceramic coatings; Rudy Irwan and H Q Sun et al. [8-9] studied the mechanical and removal characteristics of cemented carbides with nanoidentation and nanscratch, load and feedrate were regarded as the main factors to affect material removal rate.
Their mechanical properties and chemical compositions are listed in table 1.

Hydroxyapatite (HA) is also known for its electret properties [1], piezoelectricity [2-4] and pyroelectricity [3, 5].
While electret properties mean that space charge can be introduced and/or dipoles can be aligned by means of an external electric field [4], piezo and pyroelectric properties indicate that hydroxyapatite is naturally polar, confirming a prediction made from quantum mechanical simulation [6].
Disadvantages are the usually high degree of specialization and the simultaneous existence of several variables affecting the microwave measurement (temperature, density, moisture, structure, etc.) in material measurements [9].
To investigate the properties of HA in a form of coating, namely as a film, the following procedure was employed.
These spectra will be further analysed to determine the dielectric constant of HA at GHz frequencies and how different forms affect these properties.

Particularly, the swelling properties and physicochemiacl property of rubber stator determines its life.
The performance of the modified rubber is analyzed by X-ray and scanning electron microscopy. [3] and [4] does not involve the performance of rubber changed after immersion. [5] study the swelling properties of nitrile rubber stator in diesel by testing volume expansion, linear expansion and swelling morphology by scanning electron microscopy. [5] does not related to mechanical properties of rubber stator. [6] study mechanical properties and physical sensitivity of hydrogenated nitrile rubber of ESPCP stator but does not study the mechanical properties of rubber after longer immersion. [7] study the mechanical behavior of vulcanization rubber under the conditions of temperature changed, large deformation by uniaxial tensile test. [8] study reinforcement effect of zinc oxide whiskers on the comprehensive performance of NBR vulcanizate.
Results of rubber physical properties The change rate of rubber quality.
Study on swelling properties of NBR of ESPCP stator [J].
Formulation factors on the properties of hydrogenated nitrile rubber [J].

Mechanical properties of Mg alloy is the important requirment for its application and thus many foundry processing have been applied to obtain the required properties[1,2].
As shown in fig.3, the size of spherical grain is up to 90μm and the shape factor is about 1.7.
a b c d Fig.2 Partial remelting microstructures of AZ31 billets with different isothermal holding time at 595°C: (a) 15; (b)30; (c) 60; (d) 90min Fig.3 Size and shape factor of solid particles with different holding time at 595°C Heating temperature is regarded to be mainly affect the solid liquid faction of a semisolid microstructure in partially remelting.
Moreover, this parameter is expected to influence the energy and diffusion ability of solute atoms, and thus affect the primary particle size and shape factor.
However, with the prolonged holding time the obvious increase of particle size and shape factor also occurred.