Showing 10 results for saraeian
Payam saraeian, Mostafa Gholami,
Volume 15, Issue 13 (Special Issue 2016)
Abstract
Majid Azad Hassan, Ehsan Shakouri, Payam saraeian,
Volume 16, Issue 12 (2-2017)
Abstract
Today, composite materials have extensive use in aerospace automotive and defense industries compared to metals, because of their high strength to weight ratio and good corrosive resistance. Machining of these materials regard to their composite structure is complicated. Achieve optimal machining conditions, depending on the needs, according to the type of fiber and resin used in composites, need proper analysis and careful investigation. In this study, composite pipes made of glass-epoxy to a thickness of 5 millimeters, which are often used in the body of Aerospace structures, produced by hand lay-up and their surface roughness after turning process is measured. In order to obtain the minimum roughness in the turning process, tool type in two modes, and cutting speed, feed rate, and depth of cut are studied at three different levels. So Taguchi experimental design method and experimental test samples on roughness the results analysis and performed by minitab software. Finally, concluded that the minimum value of the surface roughness is obtained by tools with chip-breaking levels, cutting speed 100 m/min, feed rate 0.05 mm/rev, and the depth of cut 1.5 mm.
Volume 17, Issue 4 (1-2014)
Abstract
Mobile telecommunications tremendous growth in the 21st century made ITU define wireless communications as the driver of ICT in the world. Advent of this technology to Iran, like every other new technology, leads to superior changes in economic, socio-cultural, political, defensive and security aspects. None of the research done on national security has directly focused on mobile telecommunications industry. The aim of this paper is to propose a structural model for the enhancement of mobile telecommunications with regards to national security interests. To fulfill this aim, we first define the research question and problem solving method using systematic approach. The research guidelines are then studied one after another. After identifying influential elements and their interrelations, the development model, which is a directed graph, would be introduced using Interpretive Structural Modeling (ISM) method. Key elements of the model are: National Security, National Interests, Foresight, Understanding the Environment, Problem solving design approach, Breakthrough Thinking, Selected theory-driven development, Communications Regulatory Agency, Strategic Intentions and Upstream Documents and Macro trends. The final model presents how Strategic Intentions turn into action plans under the influence of Global Macro trends. Proposing segmentation based on different layers of the model for better implementation and the long-term effects of national decisions and accomplishments on global drivers constitute other achievements of the modeling.
Hamzeh Shahrajabian, Masoud Farahnakian, Payam saraeian,
Volume 17, Issue 5 (7-2017)
Abstract
Ultrasonic Assisted Magnetic Abrasive Finishing (UAMAF) is the combination of magnetic abrasive finishing (MAF) and ultrasonic vibrations to finish the surfaces in nanometer scale. In this work, the experimental setup for UAMAF was prepared to finish inner surface of tube workpiec. By using experimental setup, the effect of experimental parameters such as ultrasonic vibrations, mesh number, the type of abrasives (SiC and diamond) and finishing time has been investigated on the changes in the surface roughness of AL6061 tube workpiece. The experimental results showed that the use of ultrasonic vibrations has a significant effect on reducing the surface roughness. The changes in surface roughness increases with the mesh number from 90 to 800 and finishing time from 30s to 5 min. Among two types of abrasives, diamond showed the best performance in finishing. Optical microscopy images showed that the dominant finishing mechanism in MAF for coarse grains (with mesh size of 90 and 120) is two body and for fine grains (with mesh size of 220, 400 and 800) is three body. In UAMAF for both of the coarse and fine grains the dominant finishing mechanism is three body.
Arian Ehterami, Payam saraeian, Shahram Etemadi Haghighi, Mahmoud Azami,
Volume 17, Issue 12 (2-2018)
Abstract
The main purpose of using scaffolds replacement tissues of the body. The most important part is to choose the type and steel scaffolding so that eventually will replace the damaged tissue. One of the mechanisms proposed to reshape the bone is based on its piezoelectric properties. It seems that the use of piezoelectric materials is an option for use in the body, is a unique privilege. Therefore, the ceramic barium titanate (BaTiO3) having good piezoelectric properties, Curie temperature of about 125˚C and laboratory observations that non-toxic in the body, as a candidate to replace and simulate the performance of bone tissue, has been proposed. In this study, the design and produce of barium titanate piezoelectric ceramic as a bone scaffold with foam casting method and become coated with gelatinous and nanostructured HA composite for bone tissue engineering. Then test its properties by infrared spectroscopy, X-ray diffraction, scanning electron microscopy and mechanical properties were studied. In the end, it was concluded that the barium titanate scaffold produse with foam casting method coated with gelatin nano hydroxyapatite composite structure suitable for use in bone tissue engineering.
H. Hoseinpour , P. saraeian , E. Shakouri ,
Volume 20, Issue 5 (May 2020)
Abstract
Due to the specific characteristics of composite wood plastic and increasing of this product due to its compatibility with the environment, the quality of the appropriate surface area during the various machining processes on this material has been considered more than before. In this study, after turning operation with self-rotary tool on samples by changing the parameters of spindle speed, the feed rate and cutting depth, to measure and compare the surface roughness of the turning surfaces, the surface quality assessment has been investigated by microscope as well as numerical analysis of the process. The results show that during turning with self-rotary tool, for the cutting depth of 1mm and the feed rate of 22.0mm/rev by increasing the spindle speed from 500 to 710rpm, the surface quality of about 17% improved that this amount compared with conventional turning is also Improved about 37%. Also, due to increasing machining forces, by increasing the feed rate from 22.0 to 44.0mm/rev, surface quality is reduced by about 21%. Comparing the obtained values for surface roughness showed that after the feed rate, the spindle speed had the highest impact on the quality and health of the turning surfaces. Also, comparing the roughness of the measured surfaces during the finite element method and the experimental method showed the proper accuracy and adaptability of these two methods.
H. Emami, E. Shakouri , P. saraeian ,
Volume 20, Issue 7 (July 2020)
Abstract
Aluminum alloys, due to their high variety and favorable mechanical properties, are widely used in industries. Aluminum alloy 111H-5754 due to its properties such as high strength to weight ratio, ductility, toughness, and corrosion resistance, are applied in the manufacture of automotive body, offshore, and offshore oil equipment. The presence of 3% magnesium in the chemical structure of this alloy makes it susceptible to heat and therefore, it is not possible to perform most of the traditional machining processes on it. Water jet machining with abrasive particles (AWJM), because of the use of water and abrasive particles as cutting tools, can be a good method for machining these materials. In the present study, the effect of water jet and abrasive particle machining process parameters, including water jet pressure, traverse speed and loading coefficient on surface roughness, angle of striation, and burr formation in aluminum alloy 111H-5754 samples is discussed. The results showed that after traverse speed, water jet pressure and loading coefficient have the most effects on the surface quality characteristics, respectively. So, for a loading factor of 45% and a jet pressure of 300MPa, increasing the traverse speed from 200 to 300mm/min, the surface roughness value in the smooth area is about 50%, and the angle of striation of the lines in the rough area, increased by about 25%.
Ahmad Gorji, Payam saraeian, Adel Maghsoud Pour, Ehsan Shakouri,
Volume 21, Issue 3 (March 2021)
Abstract
Due to the increasing expansion of products made of plastic materials, high percentage of plastic waste enters the waste and waste annually, and the recycling of these plastic wastes is usually accompanied by decrease in their mechanical properties. One of the simplest and the most affordable ways to overcome the decline in mechanical properties during use recycled polymer, is achieving optimal combination virgin polymer and recycled polymer via mixing together. In order to produce products with both high quality and optimal mechanical properties will be desirable. Accordingly is beneficial for both environment and economic point of view, reducing use of virgin polymer. In this study, in order to investigate the effect of weight percentage of recycled polyamide 6.6 with virgin polyamide 6.6 on the mechanical properties by injection molding proses, mix recycled polyamide 6.6 and virgin polyamide 6.6 with different weight percentages is prepared and then is injected. The results of mechanical tests on injected samples showed that adding more than 50% by weight of recycled polyamide 6.6 to virgin polymeric materials increased melt flow index, glass transition temperature and crystal temperature. While, the mechanical properties of samples decreased with increasing weight percentage of recycled polyamide in the composition. These changes were less for some properties such as tensile and flexural strength and more for impact resistance. Tensile and flexural strength and impact resistance in samples with 50% by weight of recycled polyamide in the composition, respectively, decreased by about 6%, 9% and 34% compared to the new polyamide sample.
Mahdi Barghamadi, Payam saraeian, Sadegh Rahmati, Ehsan Shakouri,
Volume 21, Issue 3 (March 2021)
Abstract
Today, a variety of implants with different applications are used to replace or support a damaged biological structure, the most common of which are dental and orthopedic implants. Due to the widespread use of stainless steel 316 L in the manufacture of implants and the occurrence of cracks and residual stresses during the process of electrical discharge machining for the production of these products, the use of effective and economical polishing methods such as burnishing in It is effective in increasing the surface properties and compatibility of these products with living tissue. In this study, after performing the electrical discharge machining process on the surface of the sample and making the ball burnishing, the burnishing operations were performed by changing the input parameters and in accordance with the experiments designed using the mini tab software. Thus, the effect of variable burnishing force, feed speed and number of tool passes on surface roughness properties, micro-hardness and corrosion resistance of the final surface of the work piece were investigated. During the optimization of the response surface methodology, the optimal value for surface roughness, micro-hardness and surface corrosion rate of the samples were obtained, respectively, 0.108 μm, 435.34 Vickers and 2.18*105 respectively. Compared to the control sample, the surface roughness of the samples decreased by about 97% and the micro-hardness and corrosion resistance of the samples increased by about 2 and 11 times, respectively.
Amir Hosein Akbari, Payam saraeian, Shahram Etemadi Haghighi, Ehsan Shakouri,
Volume 22, Issue 5 (May 2022)
Abstract
Due to the difficulties and limitations in grinding hard materials, the use of nanoparticles in the Minimum Quantity Lubrication method can be effective as an appropriate solution to improve the efficiency of lubricating fluids. In this study, the effect of using a combination of carbon nanotubes and copper nano oxide on the surface quality of Inconel 718 alloy during grinding by Minimum Quantity Lubrication has been investigated.
The results showed that the use of nanoparticles in Rapeseed oil reduced the roughness and improved the surface health of the samples. The best surface topography with the least amount of pits and Furrows was obtained by combining nanoparticles with 3wt% in rapeseed oil, so that the surface roughness of the samples was reported 0.243 μm during this method, which is compared to the net use of CNT and CuO decreased by 14% and 7% respectively. Also, during the use of nanoparticles in minimum quantity lubrication, the amount of surface roughness compared to dry, flood and minimum quantity lubrication with rapeseed oil, decreased by about 35%, 13% and 18%, respectively.
