Papers by Keyword: Component

Abstract: The global market size for Additive Manufacturing is predicted to be around USD 20 billion by 2025. The question arises whether conventional machining such as Computer Numerical Control (CNC) should be replaced by Additive Manufacturing (AM). The results presented in this paper are the outcome of an ongoing study. The overall objective of this study is a decision tool to decide which manufacturing route to adopt from a sustainability perspective. This paper will discuss the first phase of this study looking at the mechanical performance, cost and complexity of parts produced from AM and CNC. The results show that small parts are cheaper to fabricate by AM regardless of part complexity, whereas large, simple parts are cheaper to fabricate by CNC machining. These results might help in identifying manufacturing limitations of AM process in terms of mechanical performance and cost. These results will serve as inputs into a decision-making framework to decide on the most effective manufacturing route based on desired application such as in the spare parts in oil and gas industry.

Abstract: Chemical and marine components are faced with corrosion resulting from salty media in an application, which ends up in serious catastrophe. In an attempt to provide and curtail this challenge of toxic use of inorganic inhibitors, properties of Artemether/Lumefantrine was examined as a corrosion inhibitor for mild steel in 0.625M sodium chloride (NaCl) medium. The corrosion propagation under different inhibitor concentrations between 0-20 ml and the temperature difference of 298-323K was examined using linear potentiodynamic polarisation and open circuit potential. The structural pitting evolution was done using a scanning electron microscope (SEM) and energy-dispersive x-ray spectroscopy (EDS) analyses. From the data, the activation energy of the corrosion reaction increased with increasing inhibitor concentration, suggesting that it inhibits corrosion by increasing the energy required to initiate the corrosion reaction. The Gibbs free energies of adsorption fall within the range of-10.08 and-13.87 kJ/mol, which is greater than-20 kJ/mol; thus, the artemether-lumefantrine inhibitor exhibited physical type adsorption. The values of the free energy of adsorption were all negative. The Langmuir Isotherm seems to perform exceptionally well with a correlation efficiency of 0.975 against all other isotherm fits.

Abstract: An analytical study on the component-level mechanical functional properties of the thermal structure connecting end frame was conducted, illustrating by advanced composite materials (ACM) C/C and C/SiC. Different grades of component-level experiments and analyses the weakness of composite connecting end frames were carried out, including the screw hole pull-out test, which mainly reflects the features of materials, the bending test of corner beams, and the corner box test with structural characteristics. The failure of different components and the factors have been obtained from this research.

Abstract: The major concern in the aviation industry is the flight safety. Although great effort has been put into the development of material and system reliability, the failure cases of fatal accidents still occur nowadays. Due to the complexity of the aviation system and the interaction among the failure components, it is difficult to do the failure analysis of the related equipment. This study focused on surveying the failure cases in aviation, which were extracted from failure analysis journals, including Engineering Failure Analysis and Case studies in Engineering Failure Analysis, in order to obtain the failure sensitive factors or failure sensitive parts. The analytical results showed that among the failure cases the fatigue failure is the largest in number of occurrence. The most failed components are the disk, blade, landing gear, bearing, and fastener. The frequently failed materials are steel, aluminum alloy, superalloy and titanium alloy. Therefore, in order to assure the safety in aviation, more attention should be paid to the fatigue failures.

Abstract: 1000 MPa grade cold-rolled duplex steel with 5 component systems was trial-produced in the laboratory. After hot rolling, pickling and cold rolling, the test steel was simulated continuous annealing on Gleeble-3800 thermal simulator. The microstructure and properties of 5 kinds of experimental steels after simulated annealing were analyzed. The results show that C and Mn elements are the basic alloy systems of all duplex steels. In the case of low Si element, the C element content of the 1000 MPa grade dual phase steel should be 0.15 % or higher, and the Mn element content should be higher than 1.8 %. Si element increased to the A3 point, while the amount of austenite was less in the two-phase region during annealing, and the volume fractionof martensiteafter the rapid cooling is insufficient; Nb element is a high-efficiency fine-grain strengthening element, which greatly improvedthe uniformity of the steel species. The fine-grained martensite islands have enhance the tempering stability of martensite and thereby to reduce the adverse strength effect from over-aging temperature.

Abstract: Optimal allocation of reliability to components of a system is one of the several ways of ensuring high system reliability in design. The problem which is typically formulated as single criterion optimisation encounters difficulty when the analytic system reliability expression is intractable usually as a result of complex system configuration. The current work re-examines a novel approach previously developed by the authors which takes a multicriteria view of the problem on the basis of the minimum cut sets of a system, and thus avoids finding the top level system reliability before optimisation. The model and methodology was applied to two complex system reliability allocation problems: a classical one and one associated with electricity transmission. The results were consistent with previously obtained ones by the authors and with the reliability importance of some notable components.

Abstract: CVD SiC material with many excellent physical and chemical properties was used widely in the field of aerospace as reflector materials. In addition, CVD SiC thin film materials because of its compact structure, high purity can also be used as precision optical components of semiconductor industry. But the CVD process is a complex chemical process and the reaction process is very time consuming. Research of chemical vapor deposition for preparing silicon carbide process mechanism is important significance for the expansion of the application of silicon carbide. In this paper, CVD SiC coatings were fabricated by the pyrolysis of methyltrichlorosilane (MTS) in hydrogen at a low pressure. XRD and EDS were used to characterize the component of intermediate. SEM was used to observe the surface morphology and microstructure of coatings. The results indicated that key problem to be solved is to control the growth rate of SiC for high quality deposition coating, while the growth rate is also affected by process parameters. To obtain the materials to meet the use requirements, the need for control of each parameter in the reaction process.

Abstract: The ceramic coating containing anatase TiO₂ and rutile TiO₂ is fabricated on the surface of pure titanium in the electrolyte of C₄H₆CaO₄-NaH₂PO₄ by micro-arc oxidation (MAO) method. The effect of different current density to microscopic structure, elemental composition and phase components of Ceramic Coating are studied with scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), 3D profilometer and etc. Results indicate that the ceramic coating on pure titanium by micro-arc oxidation is a porous mixed crystal structure which is mainly composed of such elements as Ti, O, Ca and P. With current density increasing, the average pore diameter and roughness on film surface first increase and then decrease, the porosity increases, the ratio of Ca/P then decreases, the relative content of anatase TiO₂ increases and that of rutile TiO₂ decreases.

Abstract: Glass Fiber Reinforced Plastic composites are used for pipes, high pressure vessels, aircrafts, automobiles, sport goods and Glass Fiber Reinforced Plastic composites are used for pipes, high pressure vessels, aircrafts, automobiles, sport goods and structural applications due to their high corrosion resistance, high specific strength, low density, low coefficient of thermal expansion, durability, low maintenance and low cost. This paper presents the development and mechanical testing of filament wound Glass Fiber Reinforced Plastic composite hollow cylindrical components. In this present work, Glass Fiber Reinforced Plastic composite hollow cylindrical components were manufactured by helical filament winding process. ASTM: D2584 standard test method for ignition loss of cured reinforced resins was conducted on the specimen to determine the fiber to resin ratio. The tensile test was conducted as per ASTM: D638 standard. The three point flexural test was conducted as per ASTM: D790 standard. The hoop tensile strength test was conducted as per ASTM: D2290 standard. The external loading characteristics were determined by conducting the ASTM: D2412 standard test. The tensile strength and flexural strength in the axial direction are 50.76 MPa and 425.46 MPa respectively. The hoop tensile strength and the parallel-plate loading (Compression) stiffness are 156.33 MPa and 2750 N/mm respectively.

Abstract: Cloud technology has undergone significant and rapid growth in recent years, providing users with ever more Cloud resources. The services offered are based on users’ usage habits, so users come to rely ever more on Cloud applications. OpenID Union proposed an authorization method, allowing the authorized transfer of users’ personal data from one Cloud to another, using personal registration information. However, since providers do not protect users’ private information, attackers can easily intercept and tamper with confidential messages. In this paper, we use the characteristics of the blind signature to support user verification of the registering provider, to protect the user’s identity, and to address known vulnerabilities in the system.