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Results indicate that strength, young’s modulus and extensibility of CFRP sheets deteriorated owing to climatic factors.
An average value of aging residual strength semi-experienced math model is used to study time-dependent deterioration on fiber reinforced polymer affected by climatic factors of east China.
Studies of changes in the physical and mechanical properties of two common kinds of carbon fiber reinforced polymer (CFRP) sheets after 3 years of aging under climatic conditions of east China are reported.
Physical and mechanical properties are including appearance, tensile strength, elastic modulus, elongation. 2.
Statistical results of material properties.

Expectedly, the mechanical properties of the nanocomposites have a degree improvement.
Values of the mechanical properties of each group were decided by the means of five samples.
Meanwhile the orientation of MWCNTs in PC matrix was changed, thus affected the mechanical properties of the composites.
The MWCNTs content was the most dominant factor which would enhance the mechanical property of MWCNTs/PC nanocomposites.
Besides, the mechanical properties and SEM analysis showed that the injection conditions were also one of major factors which would obviously affect the mechanical properties of MWCNTs/PC nanocomposites.

Fig.1 Principle of hot stamping The product obtained after hot-stamping has a high mechanical strength, dimensional precision and mechanical properties, no rebound phenomenon.
Analysis of factors affecting the cooling effect And the cooling rate is a measure of the uniformity of the cooling effect of mold cooling indicators.
Cooling rate is an important factor affecting the process cycle and productivity; uneven cooling causes residual thermal stress within the product, affecting its mechanical properties and service life [5]. 1.
Conclusion In the hot stamping process, the raw material to complete the transformation from austenite to marten site organization, and therefore mold cooling effect directly affects the mechanical properties and dimensional accuracy of the product.
The analysis revealed: water flow rate, pipe diameter, spacing distance pipelines and pipe work-surface is a major factor affecting the mold cooling effect.

Whereas natural rubber has superior mechanical properties that are better than synthetic rubber.
The test results showed that the mass ratio of RSS/EPDM rubber affected the mechanical properties of the resulting rubber compound.
Ozone attack causes deterioration of natural rubber which affects the properties of natural rubber.
Mechanical Characteristics Rubber pneumatic fender application is subjected to environmental factors such as sunlight, oxygen, or high temperature.
Besides mechanical properties, aging also affected the duration time of the product.

The examined Al-brasses have similar chemical composition but differ in microstructure, surface state what affects their corrosion and mechanical properties.
Fig. 1 Microstructure of the Al-brasses Surface properties The internal surface of pipes is mostly exposed to flowing liquid environment also their resistance to degradation will depend on mechanical and corrosion surface properties.
These factors have influence on mechanical properties and corrosion behaviour.
The brasses: properties & aplications. 2. ed.
Factors Affecting Corrosion and Fouling of Metal Condenser Tubes of Copper Alloys and Titanium.

Research on High Temperature Mechanical Properties of Casing in Complex Environment Deep Well Jun Wang1,a 1CNPC Jilin Oil field Oil Production Technology Research Institute, China National Petroleum Corporation, Songyuan 138000, Jilin, China aw-jun@petrochina.com.cn Keywords: Complex deep well, Casing steel, Mechanical properties, Strength reduction coefficient, High temperature Abstract.
Taking an ultra-deep field as an example, the results show that casing mechanical properties decreases with the temperature increasing; in the design process of high temperature well, the temperature effect is needed to consider.
Temperature effect of casing material properties, especially the effect variation on the Q125, V140 high grade steel tube material properties with temperature, needs to be obtained from experimental research.
Based on statistical theory [10], this experiment used five samples at each temperature for the determination of the properties.
[8] Ling Shushen, “Statistical Processing of Test Data and Error Analysis - 8th Chapter”, “Determination of the Least Number of Samples in Mechanical Properties Test”, Physical testing- physical, vol 37, pp. 544–548, January 2001

Study on the Influence Factors of Mechanical Properties of PPTA Fibers in Microscale Simulation Ying-Ying GAO1,a*, Shu-Hu,LI1,b, Jing-Li XU1,c, Hai-Yun ZHANG1,d, Yan LIU1,e, Guo-Wei LIANG1,f, Kui-Yuan SUN1,g 1Shandong Non-metallic Materials Institute, Jinan 250031, China a2365770027@qq.com, bshuhu_li02@1663.com, c94418853@qq.com, d1013057379@qq.com, eliuyan3024@163.com, f18742017200@1266.com, gsky17865316261@163.com Keywords: Poly (p-phenylene terephthalamide) fiber, macromolecular chains, multiple of cell expansion, length of bond broken, mechanical properties Abstract: Poly (p-phenylene terephthalamide) (PPTA) fiber is a high-performance aromatic polyamide fiber that has a wide range of applications in aerospace, defense, automotive and other fields.
From the above expansion model, it can be seen that the unit cell only expands in the Z direction, while the X and Y directions remain unchanged, and the molecular chains inside the unit cell continuously elongate in the Z direction. 4.3 Prediction of mechanical properties of PPTA fibers at the molecular scale 4.3.1 Prediction principle of mechanical properties of PPTA fiber unit cell structure model Principle of mechanical properties prediction method for PPTA fiber cell structure model: First of all, in order to calculate the mechanical properties of the microstructure, we wrote a set of Perl language scripts, in which a certain strain is applied to the model file first, the corresponding stress value can be obtained after calculation, and then the stress-strain results and the trajectory file in the calculation process are obtained, and then the model key length of the last frame is calculated.
Mechanical properties of crystal models with different expansion ratios Models PPTA111 PPTA112 PPTA115 PPTA1110 Tensile strength/GPa 24.25 21.29 17.4 12.54 Young's modulus/GPa 240 231 227 224 Fracture elongation rate/% 10 9 7.6 5.6 By comparing the mechanical properties of crystal models with different cell expansion ratios, it can be seen that as the cell expansion ratio increases, the tensile strength continuously decreases.
The main reason for the change in mechanical properties caused by the expansion factor is that the molecular chains inside the unit cell continue to elongate during the expansion process.
During the stretching relaxation process, the molecular chains inside the unit cell undergo segmental motion, and the molecular chain conformation changes, thereby affecting the mechanical properties of the unit cell model. 4.3.3 Comparison of mechanical properties of crystal models under different length of bond broken After the script stretching of the fiber unit cell model, the corresponding stretching process trajectory file can be obtained.

Influence of Ageing on Mechanical Properties of Epoxy Coatings Danuta Kotnarowska1, a, Małgorzata Wojtyniak1, b 1 Radom Technical University, Al.
Introduction Environmental factors, affecting polymeric coatings, induce ageing processes that lead to their destruction, what results in lower durability [1, 2].
Factors that are the most dangerous are aggressive media.
Destruction polymer coatings caused by environmental factors results in deterioration of their mechanical strength and resistance to the action of erosive particles [7, 8].
Deterioration of mechanical properties of epoxy coatings and increase of their surface roughness cause decrease of their erosive wear resistance [9, 10].

This review aims to provide an overview of the comparison of differ types of Natural fiber composites, factors that affect the mechanical, thermal and machinabilty of NFCs and their engineering applications. 1.
The main factors affecting mechanical performance of NFCs are, Selection of fiber i.e including type, harvest time, extraction method, aspect ratio, treatment and fiber content, matrix selection, interfacial strength, fiber dispersion, fiber orientation, composite manufacturing process and porosity.
Analysis on Mechanical Properties: Ajith Gopinath, et al [1] made the experiment on mechanical properties of jute fiber reinforced composites with polyester and epoxy resin.
To improve mechanical properties jute was hybridized with glass fiber.
Study on the mechanical properties of epoxy composite using short sisal fiber.

The effects of the microstructure properties on the mechanical properties of C-Si-Mn hot rolled dual phase steel are reported.
It was observed that both the amounts of the martensite and the particle size of the ferrite significantly influence the mechanical properties of hot rolled dual phase steel.
The aim of our works is to develop a modeling method for controlling the microstructure properties of C-Si-Mn hot rolled dual phase steel through the experimental trend comparison of the aforementioned two factors on their mechanical properties.
Strength of the Ferrite.Ferrite in the dual-phase steel will affects the mechanical properties greatly, grain size of the ferrite is smaller, strength and plastic of the dual-phase steel will match better.
When the volume fraction is a fixed variate, grain size of ferrite become the main factor to the mechanical properties.