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Study of Effects of Weathering Factors on Internal Structure of Rocks by Laser Ultrasonic Spectroscopy Alexander A.
Introduction Study of the effects of weathering processes on the structure and physical and mechanical properties of rocks and composite materials used in construction is very important for assessing the residual life of structural elements [1-5].
Periodic processes of freezing and thawing, saturation with water containing dissolved salts and acids, ultraviolet radiation, and periodic mechanical loads – all these phenomena lead to significant degradation of the strength properties of heterogeneous materials.
(4) As the amplitude of the reference signal depends on a number of factors varying from sample to sample (e.g. the quality of acoustic contacts, the absorption of laser radiation by the sample surface), the normalization coefficient is introduced to the formula (4).
“Factors affecting the ultrasonic intermodulation crack detection technique using bispectral analysis,” NDT & E Int. 41, 223-234

From the aspect of material chemical reaction, documents [5]-[7] describe that the chemical reaction of sulfate ion and concrete under dry-wet cycles lead to degradation of concrete mechanical properties.
Research about degradation of concrete mechanical properties under dry-wet cycles is relatively little.
Wang qin[8] studied influence of dry-wet cycles of sulfate solution on concrete erosion, it concluded that factors affecting concrete erosion rate are specimen response area, concentration of erosion solution, crystallization pressure and solution temperature etc.
In summary, domestic and foreign scholars have carried out experiments to study degradation of concrete mechanical properties after dry-wet cycles.
Conclusions 1) A series of researches about concrete mechanical properties degradation have been carried out at home and abroad.

Zikai Hua E-mail: zikai_hua@shu.edu.cn Keywords-biotribology; wear; orthopaedic biomaterial; pin on disk; wear testing Abstract Wear has been the primary failure mode affecting the long-term performance of orthopaedic implants.
Introduction Wear has been the primary failure mode affecting the long-term performance of orthopaedic implants, such as hip, knee and spine prostheses [1].
Over the years, numerous different test apparatus, called simulators, have been built to study the wear properties of different prostheses [2-5].
However, in the development of new orthopaedic biomaterials, i.e. biomecical PEEK, X-linked polymers, wear properties of the biomaterials need to be considered without the influence of implants design factors.
However, test results showed that the wear rates, or wear factors in detail, were far lower than the clinical findings [6].

In this work, mechanical properties at high temperatures and microstructures of a NAB alloy were investigated.
The mechanical properties at high temperatures in form of the plastic flow curves of the NAB alloy were characterized by a deformation dilatometer.
Thus, forming temperature is an important factor affecting the mechanical properties of the forged parts [9].
Mechanical properties of the NAB material before and after the annealing process were characterized.
Results and Discussions Table 2 Mechanical properties of as-cast and annealed NAB Mechanical properties Yield strength (MPa) Tensile strength (MPa) elongation (%) Hardness (HV) NAB (as cast) 175.4 682.4 19.3 180 NAB (annealed) 317.3 682.5 22.7 175 Table 2 shows the mechanical properties of the as-cast NAB and heat-treated NAB (annealed at 675°C).

The main factor that touch on interphase, water absorption, chemical treatment and fiber fraction which mean affect the performance of kenaf fiber as a reinforcement are discussed.
The research of natural fiber reinforced composites is growing rapidly due to their mechanical properties, low cost, processing advantages and low density.
Fiber fraction: A more previous study of the fiber content on mechanical properties of kenaf fiber reinforced composite was carried out by Nishino [14].
According to some literature [18, 19], woven fibre is have good mechanical properties compare to non-woven.
Effects of Injection Temperature on Mechanical Properties of Bagases/PP InjectionMolding Components, BioResources, (2010) Vol. 5, pp. 2097-2111

Study of PSG Thickness Uniformity Influencing Factors in LPCVD Wenlong Lü1,2,a, Zhan Zhan2,b,Xiaohui Du2,c,Ruhai Zhou2,d, Haoer Zhang2,e, Lingyun Wang2,f，Daoheng Sun2,g* 1Micro-Electro-Mechanical Systems Research Center, Xiamen University, Xiamen,Fujian, China 2Department of Mechanical and Electrical Engineering, Xiamen University, Xiamen,Fujian, China alwl1980@xmu.edu.cn,bzhanzhan_snow@163.com,c772745108@qq.com,d345325749@qq.com, e693406356@qq.com,frabitwangly@yahoo.com.cn,gsundh@xmu.edu.cn Keywords: LPCVD; PSG thickness uniformity; Surface velocity uniformity; Flow distribution Abstract.In the fabrication of SiC high-temperature sensors, the phosphosilicate glass film (PSG) is deposited on the SiC wafer as the intermediate layer, achieving the bonding of two SiC wafers.
The ease of bonding is affected by the PSG film thickness uniformity.
While to some extent, the PSG thickness uniformity will affect the subsequent bonding process.
LPCVD has a series of advantages over APCVD and PECVD in quality, thickness uniformity and mechanical property of the deposited film[2,3].
In fact, the direct flux is not completely isotropic and the supplementary reacting gas flow will also affect the thickness uniformity of deposited film.

The steel showed a same mechanical property with that of the same degree of structural strength.
However, it revealed higher structural characteristics such as mechanical, thermal properties than that of the same strength steel in a high temperature.
Thermo-mechanic control process is applied to keep the same mechanical property even if the thickness of the structural steel is over 40 mm.
Mechanical properties in high temperatures of the FR and TMC FR steel are suggested in Table 2.
The next step is that the structural stability such as deflection and a maximum load carrying performance is to be derived from the calculated surface temperatures of the beam step by step using the mechanical properties, expansion coefficients, and boundary conditions [5].

The use of hybrid composite materials has increased due to their special mechanical and physical properties.
Introduction Carbon fibre reinforced plastics (CFRP) and Fibre metal laminates (FMLs)are often used in various applications of aircraft components and structures due to their high mechanical properties material.
Theinteraction effects and significant factors of cutting parameters on the surface qualitywas graphically described.
Table 1 Control Factors and their levels CFRP/Al2024 Burr Tool 6mm dia.
The purpose of this analysis is to investigate theinfluence and interaction of machining parameters significantly affecting the performance of thesurface quality.

Achieving a uniform distribution of reinforcement within the matrix is one such challenge, which affects directly on the properties and quality of composite material.
Also the effect of different reinforcement for AMMCs on the mechanical properties is discussed in detail.
It was concluded that type and morphology of CNT reinforcements are significant factors to be considered in preparing CNT–Al nanocomposites during powder metallurgy routes [14].
Naiqin Zhaoa et.al analyzed the effect of mechanical alloying on SiC distribution and the properties of 6061 aluminum composite.
Microstructure and mechanical properties of 6061 Al alloy based composites with SiC nanoparticles were studied by A.J.

Particle size and the amount of reinforcement have pronounced effect on the mechanical properties of composites.
End Milling of the composites There are many factors affecting the machining quality characteristics in terms of surface finish and cutting forces.
Depth of cut (C), size of SiC particle (D), and interaction factors (AD) and (BC) are the most significant factors followed by feed and cutting speed for the cutting force.
Size of SiCp (D) and cutting speed (A) are the most influencing factors for surface finish and depth of cut (C) and size of SiCp (D) are influencing factors for cutting force.
Kok, Production and mechanical properties of Al2O3 particle-reinforced 2024 aluminum alloy composites, J.