Search results

In this study, to clarify the material factors affecting the fatigue strength degradation by irreversible hydrogen, we conducted the fatigue tests for cold-drawn eutectoid steels having different activation energies or microstructures.
Table 2 Mechanical properties.
Table 2 summarizes the mechanical properties.
This implies that the irreversible hydrogen content itself was not a determining factor affecting the fatigue strength degradation.
Conclusion We investigated the factors affecting the fatigue strength degradation by irreversible hydrogen in cold-drawn eutectoid steels.

Review of the Influence of Poisson's Ratio on The Solid Propellant’s Structure and Properties ZHANG Xiao*, ZHENG Jian, PENG Wei, GU Zhixu Mechanical Engineering College, Shijiazhuang 050003, Hebei, China *email: erebuss@outlook.com Keywords: SRM; structural integrity; Poisson’s ratio Abstract: In this paper, the influence of Poisson's ratio on the solid propellant’s structure and properties was summarized.
The Poisson's ratio of the relationship between structure and property of complete, using authentic data, and function in accordance with the Poisson's ratio and temperature, time, using true Poisson ratio variation, conducts the research to the corresponding changes in properties, improve the practical value of the research, and make a comprehensive analysis of multiple factors. 2．
Fig.2 Von-Mises strain of SRM with different storage time [9] Chang Wujun, et al. [10] used experimental methods of CRE and CCD microscopic analysis to study the evolution process of dehumidification damage under different tensile rate for the dehumidification question of influencing composite Q propellant’s mechanical properties under the loading effect.
They established a viscoelastic constitutive model and analyzed the internal microscopic reason of occurrence and development of macroscopic mechanical properties according to the theory of microscopic mechanics and interfacial mechanics.
However, the simulation results are affected by model, parameter setting and so forth, the credibility of the results are greatly questioned and different calculated results often differ great, therefore, it is unconvincing.

Vibrations have been reported to have a major effect on the drilling performance, affecting the rate of penetration (ROP), causing severe damages to the drilling tools and also reduces the efficiency of the drilling process.
Drillstring vibrations are extremely complex because of the random nature of a multitude of factors such as: bit/formation interactions, drill string/wellbore interactions, and hydraulic function.
Vibrations are extremely complex because of the random nature of a multitude of factors such as bit/formation interactions, drillstring/wellbore interactions, and hydraulics function.
The riser modeled as a shell element with six degrees of freedom with the same material properties as drill pipe.The dimension properties are shown in Table 2.
Table 2 Material properties and parameters used for drill pipe, riser and wellbore Drill Pipe Riser Wall Thickness, m 0.0083 0.01 Outside diameter, m 0.2032 0.5 Force, kN 100 Length, m 550 500 Rotational velocity, RPM 80&300 Fig. 1.

The aging of adhesive The aging property of adhesives directly affects the anti-aging capability of sheet.
Resilience has a greater effect on elastic modulus, static bending strength and shear because these properties are greatly affected by the mechanical contact between the wood residues, whereas it has a smaller effect on the internal bond strength, especially on that of the phenolic-formaldehyde wood residues composite.
Main aging factors to wood residues composite(1) Temperature.
It has little impacts on strength properties.
Thus,we will fully consider the factors of aging properties in wood residues composite processing such as temperature, humidity, specimen size and so on.So we can increase its value and anti-aging properties.

In order to make this problem fundamentally under control and carry out a comprehensive post-weld heat treatment work without affecting project schedule, one investigation group is set up to address the problem, conduct a fully investigation of the cause and exclude the factors leading to overheating.
The Effect of Heat Treatment to Mechanical Properties Under Different Heating Temperatures.
Samples were taken from suspected overheated area of members to examine the mechanical properties.
Mechanical Property Analysis.
The test samples for mechanical property testing are taken from weld seams of overheating regional, heat affected zone and normal base metal area respectively.

The factors working on chemical reaction affect the formation in the same.
Introduction Amorphous alloys are expressly concerned by vast number of scientific and technological researchers because of its excellent mechanical properties.
Three factors effecting on amorphous formation have been clarified as main elements [6,7].
The deposition is in better performance with complex properties of co-metal atoms.
The combination will be affected by outside conditions as main factors, but the atom outside electronic shell is crucial gene for the formation.

The effects of varying higher heat input on microstructure, mechanical properties and pitting corrosion resistance also were discussed.
Welding speed ν and focus height hf (distance of laser beam focus from material surface, positive if over the surface) were selected as factors, while the laser power P was kept constant at 12kW.
The microstructure and chemical composition of the weld metal are the most important factors which correspond to the breakdown of the passive film to the pitting resistance.
Mechanical Strength The mechanical properties, including tensile strength, yield strength and elongation, was measured from the test and the results are shown in Fig.4.
As the basic mechanical properties of normal DSS , they are high tensile strength and relatively low yield strength for all specimens.

Traditional gas nitriding of titanium alloys is carried out at temperatures above 800-900 °C and requires long-term exposures, which leads to a decrease in the mechanical properties of the material base due to structural and phase transformations [4].
It is known from a number of works [9-11] that one of the most important parameters affecting the properties of nitrided titanium alloys is a process temperature.
Thus, one of the most important parameters that control the properties of nitrided parts is their temperature during processing.
To determine the influence of titanium alloy Ti-6Al-4V ion nitriding temperature on the mechanical properties, residual stresses in the surface layer were investigated.
Technological and operational properties of titanium alloys (in Russian), Ekaterinburg, 2014

The article is devoted to the modeling of structural-phase transformations during automatic MIG welding of high-strength steel X80 in a welded seam and the heat affected zone in the ANSYS / Mechanical package.
These factors determine the low values of HAZ cold brittleness indices, which necessitated studies of the microstructure and kinetics of austenite transformation upon cooling from a temperature of 1300˚С [5].
References [1] Stolyarov V I et al 2003 Weldability of high-strength steels for gas pipes of large diameter Problems of ferrous metallurgy and materials science 3 pp 39-47 [2] Efimenko L A et al 2009 Weldability study of high-strength pipe steels of strength category X80 Welding production 2 pp 3-7 [3] Cheprasov D.A. et al 2012 Thermodeformational welding cycles and structural-phase transformations in low alloy steels of the bainitic class Polzunovsky reading 1 pp 45-53 [4] Naumenko A A et al 2012 Formation of the structure and complex of properties of cold-resistant steel for pipes of strength class X80 during thermomechanical processing Abstract, diss. ... cand. tech.
(Moscow: Bauman moscow state technical university) p 24 [5] Velichko A A 2014 The role of thermal parameters of welding in the formation of the morphology of the microstructure and the properties of the heat-affected zone in the production of longitudinal pipes Diss ... cand. tech. sciences. 05.16.01.
Darmadi 2014 Residual stress analysis of pipeline girth weld joints: Dissertation submitted for the Degree of Doctor of Philosophy thesis, School of Mechanical, Materials and Mechatronic Engineering University of Wollongong p 289 [8] GOST ISO 3183-2012 Steel pipes for pipelines.

It was shown that the addition of nanoparticles of titanium carbide improves the mechanical properties of the initial alloy, without significantly reducing the electrical conductivity (no more than 30%).
Factors that affect the value of electrical conductivity were indicated above; hence we can indirectly judge the uniformity of distribution of the reinforcing phase TiC, absence of conglomerates ofTiC particles and the purity of the obtained ingots.
This article presents the results of the study of mechanical properties of the obtained composites.
Thus, aluminum alloys modified by TiC nanoparticles are characterized by high level of conductivity and other physical and mechanical properties.
Mazaheri, RMeratian, A .Emadi, R.Najarian, Comparison of microstructural and mechanical properties of Al–TiC, Al–B4C and Al–TiC–B4C, Materials Science and Engineering, 2013.- Vol.A 560.- P.278-287