فهرست مطالب

Modern Processes in Manufacturing and Production - Volume:5 Issue: 3, Summer 2016

Journal of Modern Processes in Manufacturing and Production
Volume:5 Issue: 3, Summer 2016

  • تاریخ انتشار: 1395/08/30
  • تعداد عناوین: 7
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  • Hamzeh Shahrajabian, Masoud Farahnakian*, Mehdi Moghri Pages 5-11
    During the past decade, polymer nanocomposites have emerged relatively as a new and rapidly developing class of composite materials and attracted considerable investment in research and development worldwide.Direct machining of polymers can be an option for personalized products and for manufacturing product samples. To obtain high quality products and reduce machining costs, it is very important to understand the machining conditions so as to achieve enhanced machining performance. The influence of machining parameters (feed rate) and tool type (cemented carbide, HSS and coated HSS) on thrust force in drilling of epoxy, epoxy/clay and epoxy/TiO2nanocomposites are investigated. Variation of input parameters, feed rate and tool type affects the thrust force. The cemented carbide tool creates less thrust force than HSS and coated HSS tools. The thrust force in drilling process of epoxy/TiO2nanocomposite was more significant than epoxy resin and epoxy/nano clay. The minimum thrust force (13 N) was obtained in feed rate of 0.02 mm/tooth in neat epoxy with carbide tool.
    Keywords: Drilling, Machining Parameters, Tool Type, Nanocomposites
  • Moslem Tayebi, Hesam Moghadasi, Davood Rahmatabadi, Enayatolah Mohemi, Ramin Hashemi * Pages 13-21
    In this paper, the reasons of damage water pumps parts of the air compressor cooling system were studied. To reach this goal, the works like preparing metallographic samples, evaluation of structure, investigation of mechanical properties, the alloy parts detection and chemical analysis of deposit and corrosion products collected from the parts were performed. According to studies and results obtained, alloys suggested to be used in the impeller and casing are gray cast iron with flake graphite (random distributed) and ductile iron with spherical graphite (distributed almost uniformly), respectively. Also cause damage to the pump impeller, graphitic corrosion was described.
    Keywords: Impeller, Casing, Graphitic Corrosion, Gray Cast Iron, Air Compressor Cooling System
  • Javad Shahbazi Karami *, Nazanin Kafaei Kavoshian, Afshin Kazerooni, Akbar Ghazi Mir Saeed Pages 23-39
    Sandwich panel with central core honeycomb aluminum as one of the main shielding structures because of their high strength-to-weight ratio and improved energy absorption capacity, has been attracted the attention of many researchers and practitioners in recent years. This paper initiates and presents a new type of central core honeycomb formed by hydroforming process. The study is augmented by a numerical and experimental work on flexural behavior of sandwich panel structures made of aluminum alloy and different cores such as aluminum, polyurethane foams, PVC, silicone and carbon fiber. Firstly a numerical simulation by ABAQUS software was run, then prepared samples were tested and related force-displacement diagrams were depicted from results. Comparing the corresponding diagrams obtained from simulation with that of the results of experimental investigation, high flexural strength of the sandwich panels with proposed honeycomb core relative to a three-layer sheet as well as a very high flexural strength of suggested sandwich panel with honeycomb core filled with carbon fiber against other samples of honeycomb was observed. Finally, comparing the experimental results with numerical simulations indicates acceptable conformity.
    Keywords: Honeycomb Sandwich Panels, Flexural Behavior, Hydroforming
  • Amin Rabiezadeh*, Ahmad Afsari Pages 41-57
    In this research, surface composite layers containing nano sized TiB2, Al2O3-TiB2, ZrO2 and CNT particles have been fabricated on Aluminum alloy substrates by friction stir processing. The effects of different processing variables such as number of passes and strengthening particle distribution, hardness, and wear properties of surface nanocomposite layers have been evaluated by electron microscopy, hardness, and wear test. Results showed that surface properties of aluminum alloy will be enhanced and the optimum conditions of properties which can be determined by comparing the effects of different parameters will be obtained. An increasein the number of passes up to four modifies microstructure and accordingly mechanical and wear properties were enhanced.Surface composite produced by FSP significantly improved the dry sliding wear resistance of the Al 6061 alloy by changing the wear mechanism. The FSPed sample with Al2O3-TiB2 particles had higher wear resistance in comparison with those with TiB2, ZrO2 and CNT. This enhancement is a consequent of better bonding between particles and aluminum matrix and higher microhardness.
    Keywords: Aluminum Alloy, Friction Stir Processing, Titanium Diboride, CNT, Zirconia, Wear Properties
  • Javad Jafari Fesharaki *, Seyed Ghasem Madani, Said Golabi Pages 59-68
    This research develops thermo-elastic analysis of a functionally graded cylinder under thermo-mechanical loadings. Heat conduction equation in cylindrical coordinate system is solved. Thermal conductivity coefficient is graded along the radial direction. By considering a symmetric distribution of temperature, loading and boundary conditions, strain-displacement and stress-strain relations can be developed. Material properties such as modulus of elasticity are graded along the radial direction. For validation of the obtained results; a complete numerical analysis using finite element approach is presented.
    Keywords: Thermo-Elastic, Functionally Graded Materials, Cylinder, Stress, Strain
  • Amir Amini *, Alireza Alinezhad Pages 69-82
    In order to survive in today's competitive world, organizations are looking to increase their efficiency and effectiveness. Therefore, they should focus on inputs that are more important than the rest of the inputs in their success. This paper aimed at ranking 7Ms (Management, Man power, Marketing, Material, Machinery, Methods and Money) and their sub-criteria of production in Iran. By improving manufacturing processes, manufacturing organizations create and establish their added value. The Analytic Hierarchy Process (AHP) is a very popular method in decision making process, and its inner dependence extension is used for cases in which criteria or alternatives are not independent enough. In FAHP, each option severity is displayed by fuzzy numbers in relation to criteria. Therefore, a fuzzy judgment matrix is obtained. In this study, Fuzzy AHP tool has been used to rank these inputs. The results are compared with the ideal ranking results and are examined that how different they are.
    Keywords: ranking, 7Ms Effective Factors, Production Systems, MCDM, Fuzzy AHP Method
  • Reza Nosouhi *, Saeed Behbahani, Saeid Amini, Mohammad Reza Khosrojerdi Pages 83-92
    A new dynamic friction model for modeling of elliptical vibration assisted turning (EVAT) was developed in this research. The periodic change of the friction force direction is known to be one of the most important causes of this phenomenon. In modeling of machining processes (including the EVAT process), static Coulomb friction model was employed by most of the researchers. Because of the periodic change in the friction force direction during the elliptical vibration path, the simple Coulomb friction model could not reflect the dynamic friction phenomena between the chip and the tool such as stick-slip and dynamic breakaway. In this research the LuGre dynamic friction model, which had been successfully employed for modeling of EVAT process, was modified in compliance to the machining process. To modify the LuGre model, the LuGre model coefficients were modified so that the effect of the temperature change of the contacting surfaces (which plays a key role in the friction behavior between the chip and the tool) could be reflected by the model. To determine the coefficients, orthogonal machining tests were performed and the Genetic Algorithm optimization method was carried out to derive the coefficients. Afterward, the results achieved from both dynamic models were compared with experimental results and Coulomb model results. The results from the new modified LuGre model were in better agreements with the experimental results.
    Keywords: 2D Vibration Assisted Turning, Friction, LuGre Model, Genetic Algorithm, Orthogonal Cutting