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This paper reports the development of Monte-Carlo models of how pitting corrosion affects the location of fatigue failures in two fatigue specimen geometries that have different stress concentration factors (kt).
According to Opie [7], the gross stress concentration factor of the outer holes is 2.69 while that of the central hole is 2.48, which is 7.8% lower.
The stresses displayed in this figure are numerically equal to the stress concentration factor as the specimen is under a nominal gross-section stress of 1 MPa.
Next it will be necessary to characterize the fatigue crack growth and microstructural properties of the 7050-T7451 material from which the specimens have been made.
Computational Methods in Applied Mechanical Engineering 197 834-845 [14] Walker, K. (1970) The effect of stress ratio during crack propagation and fatigue for 2024-T3 and 7075-T6 aluminum.

Compared to glass, carbon with its captivating properties was more prevalent from then onwards.
These laminated composites showed significant properties in comparison with random oriented composites.
This laminated structure behaves much the same as a simple metal structure, but with considerable specific advantages with regard to properties, such as metal fatigue, impact, corrosion resistance, fire resistance, weight savings and specialized strength properties.
Their efficient use as structural material has been restricted due to less known factors about buckling design criteria.
The knowledge about these factors would aid in stable design of structural components like aircraft fuselage, helicopter rotor blades, missiles, stiffeners [5].

Investigation of the Influence of Technological Regimes of High-Temperature Firing on the Structure and Properties of Silicate-Enamel Coatings for Carbon Steels А.V.
Troitskaya d. 108a, Novocherkassk, Russia aannet20002006@yandex.ru, blyudmila.clim@yandex.ru, cdima.golovko9898@mail.ru Keywords: silicate-enamel coatings, structure and properties of coatings, steel protection, carbon steels, high temperature firing.
With the constantly increasing requirements for the technical and operational properties of enameled products in the production of steel pipelines, it is advisable to use single-layer enameling, which saves raw materials and energy, due to the reduction in the number of layers and firing cycles of products.
The purpose of these studies was to study the influence of technological regimes of high-temperature firing on the structure and properties of silicate-enamel coatings.
It is known that iron oxides FeO, Fe3O4, Fe2O3 included in it are characterized by various chemical, physical and thermodynamic properties (Table 1).

Under the conduction of fatigue loads, the native microscopic defects (joints, cracks, holes) continue to expand and newborn micro-cracks constantly nucleate and expand which makes the rock mechanical properties deterioration gradually.
Upper limit stress S, stress amplitude R, cyclic number n, material properties a and environment T which affect the results of fatigue tests greatly were considerate comprehensive by using residual stiffness method.
And, its DV is the function of these factors mentioned above, viz., D=D(S,R,n,a,T).
This model can attribute the impact of many factors on rock fatigue to the attenuation of dynamic modulus, thus, is convenient for engineering applications.
He: Effects of cyclic dynamic loading on the mechanical properties of intact rock samples under confining pressure conditions[J] Engineering Geology, 125, (2012), p.81-89.

The shear tests were carried out using Universal Testing Machine to evaluate the effect of Bi addition on the mechanical properties of examined solder alloy.
With the Bi content increasing, the microstructure of solder alloy has significantly been refined and the volume fraction of the Bi-rich phase appearing darker color in the image has increased (Fig. 2B-D), which will play a decisive role in the mechanical properties of the solders.
It has been confirmed that the microstructural change would affect some properties of the solder alloy.
Baraton, Effect of silver content and nickel dopant on mechanical properties of Sn-Ag-based solders, The Electronic Components and Technology Conference. (2008) 485-490
Liu, The microstructure and properties of the Sn-xBi-0.9Zn-0.3Ag lead-free solders, J Mater Sci-Mater El. 22(2011) 592-595.

Bond strength and its factors The mechanics of bond stress transfer between FRP reinforcement and concrete has been investigated extensively.
Benmokrane et al. [11] did experiments on the mechanical properties and bond strength of carbon fiber fiber reinforced polymer on the mechanical properties and bond strength of new generation of carbon fiber reinforced polymer (CFRP) reinforcing bars used as nonprestressed reinforcement for concrete structures.
Brahim, Influential factors of bond properties between fiber reinforced polymer (FRP) rebars and concrete, Industrial Construction. (2001)
[10] Javier malvar L, Tensile and bond properties of GFRP reinforcing bars.
Lord, Mechanical and bond properties of new generation of carbon fibre reinforced polymer reinforcing bars for concrete structures.

A comprehensive theoretical study was first conducted to evaluate the influence of three variables (temperature (T), pressure (P), and retention time (te)) to identify the most significant factor affecting on separation efficiency.
Peng–Robinson Equation of State (EOS) was used to estimate K-values, vapor pressure, and liquid density, based on critical properties and acentric factors [38, 39].
Using the EOS (Eq. 1), the thermodynamic properties of both phases were estimated [40].
[35] Gutierrez, J.P., et al., Thermodynamic Properties for the Simulation of Crude Oil Primary Refining. 2014
[40] McCain Jr, W.D., Properties of petroleum fluids. 1973

Such connection joints cannot be treated as a rigid interface; on the contrary, they form weak links between components and greatly affect the overall stiffness and mechanical characteristics of the assembled structure [5].
Kh represents the Hertz constant and is determined from the contact geometries and material properties of the contact bodies [10,11].
Any factors that can alter the preload state of the linear guide are expected to cause a variation in the bearing stiffness of the rolling elements, hence affecting the dynamic characteristics of a feeding stage.
It is found that the first three vibration modes were slightly affected by the preload of the linear guides.
However, vibration frequencies of the higher modes are greatly affected by the preload of the linear guides.

Previous studies [3-6] had been greatly focused on machining of Ti6A14V and their research issues can be summarized as: 1) mechanisms of material removal and chip formation, 2) wear behavior of tool and chemical reactions in the contact zone between cutter and workpiece, 3) cutting forces, vibrations and temperatures during milling and their affecting factors, 4) integrities of milled surface and their influential factors, 5) high speed milling and new tool technologies.
The workpiece used is Ti6A14V titanium alloys, whose mechanical parameters are given in Table 1.
For analyzing the affecting weight of each cutting parameter, an empirical equation is used for regressing and the result is described by Eq. 1.
Ra=1.7322vc-0.0285ar0.2461vr0.198 (1) (a) with feed per revolution (b) with radial cutting depth (c) with cutting speed Fig. 2 Influences of cutting parameters on surface roughness ar D θmax θ fz vc Ti6Al4V Cutter θmax Equal area hm a b h a b Fig. 4 Illustration of the contact zone between cutter and workpiece and the average cutting thickness It can be seen from Eq.1 that the primary affecting factor on surface roughness is the radial cutting depth and the least one is the cutting speed.
Among cutting parameters, radial cutting depth is the most influential factor on surface roughness while cutting speed is the least.

In DSSC applications, platinum (Pt) is often chosen as the CE because of its excellent catalytic properties and stability.
Nonetheless, while numerous studies have focused on CE metal oxide materials in DSSC solar cells, there has been limited research on how varying Fe3O4 concentrations in rGO/Fe3O4 nanocomposites affect the characteristics and electrical properties of the resulting materials.
The optical properties and bandgap energy values of rGO/Fe3O4 nanocomposites were analyzed using UV-Vis spectroscopy.
Enhanced catalytic properties can boost DSSC efficiency by accelerating the I3- to I- reduction process at the CE surface.
Maleki, and I, Zare, Effects of mechanical properties of carbon-based nanocomposites on scaffolds for tissue engineering applications: a comprehensive review, Nanoscale Adv, (2024)