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For High altitude airship (HAA) with long time affected by space harsh environment, due to the occurrence of natural light radiation aging physical and mechanical properties, fiber-reinforced airship envelope material results in degradation of the mechanical load performance, even causing damage to the balloon airship.
The high-altitude aerostat is affected by many environmental mechanisms leading to the degradation of the mechanical properties in this space [2].
Due to the influence of multi-spectral factors, physical and chemical properties and mechanical properties of materials generated irreversible aging [3].
This paper mainly for fiber-reinforced high-altitude airship envelope material carried out the mechanical properties aging tests and the aging process morphology analysis under natural light conditions to obtain the airship envelope material mechanical properties in different axis angle 0°and 90°direction.
The test to get envelope material mechanical properties after aging using is adopted uniaxial stretching method.

During the sintering, rigid reaction products can be formed which are very harmful to the mechanical properties.
By logical examining the relationship between technological steps, we can pick out the factors influencing the product's properties (such as porosity).
All factors, which contribute to the desired properties/product, have to be marked.
Consequently, the diagram is suitable for mapping technological problems, since it takes into account all factors that may affect the properties.
By understanding their mechanism, the amount of porosity can be reduced, preventing the deterioration of the mechanical properties.

The concrete conglomerate properties change over time and depend on a number of factors.
It is known that many factors affect the stress field heterogeneity.
Its properties change over time and depend on humidity, ambient temperature, and other factors.
Thus, existing proposals come down to the fact that the elastic modulus is mainly affected by the properties and relative content of the aggregate, and the composition and properties of cement stone do not have a noticeable effect.
Bridzhmen, Study of large plastic strains and fractures: the effect of high hydrostatic pressure on the mechanical properties of material, 2010

Key factors such as printing speed, powder granulation, and laser power can greatly affect the final quality of the printed parts, including their dimensional accuracy, porosity, hardness, and microstructural characteristics[1,3].
However, each reuse cycle degrades the quality of the powder, affecting critical properties such as flowability and particle integrity.
Structural and Mechanical Challenges Porosity and Defects represent a significant challenge in metal 3D printing, directly affecting the mechanical properties and long-term reliability of printed components.
Microstructure Control is another critical factor in achieving desired mechanical properties.
Influence of powder granulation on the mechanical properties of components produced by SLM.

This variability can be attributed to various intrinsic factors, such as the plant variety, its maturity, and the cultural and climatic conditions, as well as extrinsic factors, particularly the shape of the cross-sectional area of the fiber bundles [13, 14].
The results indicate that leaf-derived bundles exhibit the best mechanical properties.
The authors noted that degradation of the middle lamella, associated with hydrolysis and depolymerization processes, affected the elastic properties of the bundles.
Effect of heat treatment on the mechanical properties of jute yarns.
Mechanical properties of chemically-treated hemp fibre reinforced sandwich composites.

The molecular structure of thin film surface composition were detected and analyzed by Fourier transform infrared spectroscopy (FTIR); and the barrier properties of the films were examined by MOCON water vapor permeability testing instrument, also，the relationship maps between permeability and process parameters were drew and the process parameters were optimized; The mechanical properties of thin films were tested by electronic tensile testing machine, and the curves of the relationship between the mechanical properties and process parameters depicted.
The mechanical properties of thin films were tested by the electronic tensile testing machine RGD-X005, whose elastic modulus precision was 0.01GPa and yield strength was 0.01MPa.
Among all the factors, background pressure, RF power, the sputtering pressure, the deposition time and the sputtering power had a great effect on the gas barrier property.
So the performance of SiOx/PET thin films was seriously affected.
The important technical effective factors of magnetron sputtering SiOx film included deposition time, sputtering pressure, and sputtering power. 2.

The model indicates that the main factors of crystal detachment are vibration frequency and amplitude as well as cooling temperature of the chilling solid surface.
The effects of the above three factors on the actual crystal detachment behaviors were studied experimentally by using a transparent NH4Cl-70%wtH2O alloy.
Introduction Crystal structure in castings is of vital importance for its processing and application properties.
The main factors determining crystal detachment were also discussed.
Conclusion Through the primary phase on the grain stress analysis , A solid surface crystal chill free mechanical model in the vibration conditions was established, it is found that the main factors affecting the free crystal include vibration frequency , amplitude, chilling temperatures and surface state, in which the vibration frequency of the maximum amplitude of Secondly, chilling temperatures and relatively small surface state .Experiment investigated crystal chill free behavior of NH4Cl-70wt% H2O solution on the surface of LY12 aluminum alloy, the experimental results with theoretical models get a better fit .

Introduction Thermoplastic materials, especially those of the polyethylene (PE) type, have become in recent years the most used for the construction of pipeline systems for the circulation of natural gas, due to their many properties that are important advantages compared to metal, such as: lower density, high chemical and corrosion resistance, easy and fast welding possibilities, relatively low assembly and maintenance costs.
The optimization methodology is a set of mathematical and statistical techniques that are used to establish a relationship between objective functions and controllable factors.
The influences of two of the controllable factors on an objective function can be presented in the form of three-dimensional graphs on surfaces.
Table 2 shows the optimal values of the controllable factors that satisfy the requirements imposed on the objective functions.
Barczy, „A study of structure and mechanical properties of welded joints in polyethylene pipes,” Materials Science and Engineering A 419, pp. 138–143, 2006

Industrially processed doped-tungsten wires in the as-drawn condition have essentially a <110>-fibre texture with attractive mechanical properties.
An attempt was also made to determine if texture weakening has any effect on the mechanical properties of the wire at room temperature.
The room temperature mechanical properties are listed in Table 2 for the three diameters ∅C, ∅D and ∅E.
Table 2: Table showing mechanical properties obtained from torsion test at an effective strain rate of 2.7 x 10-2 s-1. 5 15 25 35 45 %-reduction ∆-factor Wire diameter Reduction (%) 0 1 2 3 4 5 ∆∆∆∆-factor Fig. 6: Mapping of ∆-factor and drawing reduction as a function of wire diameter.
And the present study shows that the high ∆-factors could weaken the texture.

These stress intensity factors are also affected by the mutual interactions between adjacent cracks.
Welded Joints, Their Geometrical Characteristics and Fatigue Properties Welded Joints.
Table 1 shows the chemical composition and mechanical properties obtained from the quasi-static tensile test.
Table 1 Chemical composition and mechanical properties of SM490B Chemical composition (mass contents in %) Mechanical properties C Mn P S Si Ni Cr Mo σy (MPa) UTS (MPa) Elongation (%) 0.155 1.304 0.017 0.010 0.423 0.032 0.038 0.018 0.423 0.032 0.038 ∆ ∆ ∆ (a) Cruciform joint (b) Cover plate joint (c) Longitudinal stiffener joint Fig. 1 Configuration of welded joints Geometrical Characteristics.
Fatigue Properties.