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The prepared nano high polymer resin and carbon cloth were made into nano-prepreg by using ultrasonic impregnation method, and a nano-prepreg composite material was prepared by using hot compacting and cut to test pieces to measure its mechanical properties and surface conductivity as well as the influence of temperature-humidity environment (85˚C/168hr and 85˚C/85%RH/168hr) on mechanical properties.
Current studies on carbon aerogels mostly focused on the thermal properties and adsorbability.
Therefore, this study aimed to examine the synergistic effect of making carbon aerogels of different proportions (0, 0.025, 0.1, 0.25 phr) and PEO (0.5 phr) modified phenolic resin and carbon cloth into nano-composite, especially the influence on mechanical properties after the surface conductivity and mechanical properties are affected by temperature-humidity environment.
When the phenolic resin is immersed in a supersaturated moisture environment, the adhesive force of resin would decrease, and shrinkage occurs in the vertical direction of pressure that results in microcracks, all the above factors would reduce the tensile strength of material rapidly.
PEO modifying agent forms netty crystals in phenolic resin, although it can improve the mechanical properties of phenolic resin, in such a long-term high temperature and supersaturated moisture environment, the hydrogen bond and oxygen are combined into long chain -OH- radical that reduces the mechanical properties greatly.

Mechanical properties of ECAP materials Strength and plasticity of the ECAP material Among tests of the mechanical properties of ultra-fine grain materials, the tensile test is the most frequently conducted.
General metal and alloy material is difficult to own both of the two mechanical properties,and several ultra-fine grain materials have the mix of these two mechanical properties in materials science research in recent years.
After long-term and a large amount of research, the researchers found that there are a variety of factors which affect the fatigue strength and fatigue life.
The main factors are the following aspects: Firstly, affected by the parts working conditions, these influencing factors mainly are four aspects including load characteristics, load frequency, the service temperature and environmental media ; Secondly, affected by the parts and materials essential factors, these influencing factors mainly are four aspects including chemical composition, metallography microstructure, fiber orientation and internal distribution of defects; Thirdly, affected by the parts-state, these influencing factors mainly are five aspects including the gap effect, surface roughness, parts heat treatment, residual stress and residual strain .
Since there is a variety of factors which affect the materials fatigue properties, there are not an effective methods and techniques to avoid and reduce the hazards of these factors on the material lifetime so far yet.

A factor affecting the hardness was the most PWHT temperature 550 ๐C and PWHT time 10 hr. of 279 HV.
The properties and weldability of these steels depend mainly on carbon content.
Mechanical properties were tested by vickers hardness following ASTM E92-82(2003) standard test method for vickers hardness of metallic materials [5].
The experimental design of full factorial design to be the main factors effectors affecting significantly.
Factors affecting the hardness are the most PWHT temperature 550 ๐C and PWHT time 10 hr. were hardness of 279 HV.

The effects of Y and Nd on microstructure and mechanical properties of AJ62 alloy were investigated.
Rare earths have important affects to magnesium alloys, which can refine dendrite and improve casting capability and elevated temperature properties [6].
In this study, the effects of Y and Nd elements on microstructures and mechanical properties of Mg-Al-Sr alloys were investigated.
The increment of the deformation resistance means the increase of strength, hardness and other mechanical properties of alloys.
Thus, the alloys still have good mechanical properties at elevated temperature.

The microstructure and properties before and after laser remelting were studied.
The use of high-energy density laser beam mix the alloy of different compositions and properties together with the substrate surface, generating an alloy layer with completely different compositions and properties between substrate surface and the substrate.
As phase constitution changed, properties of laser remelting coatings also changed, mainly reflected physical and chemical properties of α-Al2O3 material.
As hardness and bond strength, the two main factors influencing the wear resistance of the coating, improved by a big margin, the wear resistance of the coating improved substantially.
The two most important factors affecting wear resistance were hardness and bond strength.

The low carbon steels were smelted with special oxide introduction technique and the HAZ properties has been studied with thermal simulation.
The optical microscope, SEM and TEM were used to analyze the composition, size and distribution of the inclusions, and the mechanical properties after thermal simulation were also investigated.
These two factors are the main causes to improve the toughness of heat affected zone for steels produced by oxide metallurgy technique.
However, after welding (especially the large heat input welding), the weld heat affected zone (HAZ) has undergone high-temperature reheating process, and the parent material’s fine-grained microstructure has been broken as the austenite grain in this region grow up seriously.
The HAZ properties had been studied with thermal simulation.

Experimental One of the most important properties of geotextile is durability; it determines the ability of a material to resist the effects of various factors throughout service life.
There are many factors that affect the durability.
The main factors are mechanical, physico-chemical and biological [21].
Mechanical factors include: mechanical damages during installation; creep; strength of the seams and joints of the material structure elements.
Physico-chemical factors: low or high temperature; effect of weathering exposure; effect of aggressive environments; The effect of these factors is extremely important in the design of structures using geosynthetics.

The main factors affecting mechanics properties and pervious coefficient of pervious concrete prepared by recycled aggregate were analyzed systematically in the paper.
Table 1 Physical and mechanical properties of recycled aggregate with the grain size range of (5～31.5mm) Apparent density [kg/m 3] Packing density [kg/m 3] Void Ratio [ %] Water absorption Ratio [ %] Crushing value [ %] 2550 1410 45 3.7 21.3 Experimental Methods Study on the Factors Influencing Mechanical Properties and Pervious Coefficient of Pervious Concrete with Recycled Aggregate.
The main factors that may influence mechanical properties and pervious coefficient of pervious concrete is aggregate to cement ratio (A/C), sand to aggregate ratio (S/A)and water to cement ratio (W/C) through analyzing the design theory of mix proportion of concrete.
The mix proportion parameters and properties of the road brick specimens were presented in Table 6.
·Theory analyses and test results indicated that the main factors on mechanical properties and pervious coefficient of pervious concrete with recycled aggregate were aggregate to cement ratio, sand to aggregate ratio and water to cement ratio.

During the sintering process, the formation and growth of elongated β-Si3N4 grains are affected by some factors, such as the number of the β-Si3N4 nuclei, the intergranular space and the liquid for the growth of nuclei.
Recently, many studies have revealed that the ideal β-Si3N4 seed is one of the most important factors for producing self-reinforced Si3N4 ceramics [4-10].
The mechanical properties of porous Si3N4 ceramics were also investigated.
Conclusions The effects of β-Si3N4 seeds on the microstructure and mechanical properties of porous Si3N4 ceramics were studied.
With the increase of β-Si3N4 seeds up to 3 wt.%, under the porosity of about 42%, superior mechanical properties, 315.98 MPa, were obtained for porous ceramics with the microstructure of fibrous grains and the average aspect ratios of 6.42.

Varying the laser processing modes makes it possible to redistribute alloying elements in the surface layer, providing special physical and mechanical properties.
Numerous factors affecting the parameters of surface roughness include the mode and type of machining, the tool used and its material, its geometrical parameters, the composition of the coolant, the rigidity of the "machine-device-tool-component" system, the composition and properties of the processed material, and a number of other factors.
In specific cases, any of the factors noted may have a decisive influence on the roughness parameters.
Obviously, this is due to the peculiarity of structural transformations related to high dispersion and isotropy, as well as an increase in wear resistance and other physical and mechanical properties.
Gozbenko et al., Physical and Mechanical Properties of Engineering Materials Using Innovative Methods, Int.