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Modern Processes in Manufacturing and Production - Volume:3 Issue: 3, Summer 2014

Journal of Modern Processes in Manufacturing and Production
Volume:3 Issue: 3, Summer 2014

  • تاریخ انتشار: 1393/09/18
  • تعداد عناوین: 6
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  • Mona Ganjali, Hadi Shirouyehzad, Arash Shahin Pages 5-16
    With development of technology and science and continuous increase in productivity, product life cycles are shortened and customer demands are more personalized and diversified, which makes companies face with ever changing and unpredictable competitive environment. Therefore, rapid response to market competition has become one of the main focuses and the competitive advantages. Today, one of the most important issues in supply chain is reverse logistics, which includes all operations related to the reuse of products and materials. The concept of reverse logistics has received growing attention in the recent decades due to a number of factors such as Competition and marketing motives, direct economic motives and concerns with the environment. Reverse logistics has become an important source of opportunity for companies to improve visibility and profitability and lower the costs across the supply chain.Environmental issues are also increasing awareness of the importance of reverse logistics. More companies are now considering reverse logistics as a strategic activity because it can create value. Since agility becomes one of the most important tools for sustainable development of companies, achieving high agility of reverse logistics enterprises is an effective means of reducing costs and better meeting consumer needs for enterprise. Therefore, constructing high agile reverse logistics systems is very necessary. The problem of how organizations can successfully deal with unpredictable, dynamic, and constantly changing environments has been a prevailing topic both in industry and academia for the last decades. This paper introduces indexes of agile reverse logistic, and then analyses the interaction between indexes by using ISM. The results were obtained through a questionnaire from the experts. The obtained results reveal that the application level of the information system of reverse logisticsandthe time of starting reverse logistics system are two undeniable needs for the agility of reverse logistics.
    Keywords: Reverse logistics, Agility, Indexes of agile reverse logistics, ISM
  • Mousa Amini, Alireza Alinezhad, Sepideh Ghasemian Pages 17-40
    A supply chain is composed of a complex sequence of processing stages, ranging from raw materials supplies, parts manufacturing, components and end-products assembling, to the delivery of end products. In the context of supply chain management, supplier selection decision is considered one of the key issues faced by operations and purchasing managers to remain competitive. Therefore, requirements of engineers or customers may result in product configuration change with product life cycle. Effective management of product configuration can actually enhance productivity and customer satisfaction. This study proposes a two-phase model in the first phase of which an innovative design for new parts will be proposed by contradiction matrix, and translating contradictions into 39 engineering parameters of TRIZ , solving them by 40 innovative principals and by means of AHP fuzzy. In the second phase, an appropriate supplier for new product will be selected by value engineering and target costing. Finally, a case of clutch system in SUPCO is used to approve the applicability of the proposed approach. In this study, the best choice is the use of fuzzy AHP. After determining the total cost of the target product and initial screening of the suppliers based on that, the index values are calculated for each supplier according to the criteria of the organization. Thus, the best suppliers with the highest value to the organization have been selected.
    Keywords: TRIZ, Product configuration change, Fuzzy AHP, Target costing, Value engineering
  • Mehdi Salari Pages 41-52
    Electrical steels are important alloys widely used in electrical instruments. The magnetic properties and low core loss of grain oriented silicon steels are closely related to the sharpness of Goss texture ({110} ).The direction of is the softest direction for magnetism. In this work, the microstructure and dependence of orientation density along the major texture fibers on the applied cold rolling sequences in the CRGO samples were investigated. Variation of the hysteresis losses revealed that hysteresis losses were high for the specimen treated at higher secondary cold reduction. In this sample, the conditions for selective growth of Goss oriented grains are violated which leads to development of grains with random orientations almost equally. The results also indicated that the annealing of the cold rolled specimen at the higher first cold reduction and lower secondary reduction showed increase of the {110}texture component intensity and drastically decrease in hysteresis losses.
    Keywords: Magnetic Steels, Grain Oriented –Texture Evolution, Goss texture– Hysteresis Losses
  • Mohammad Heydari Vini Pages 53-60
    There is a complicated relation between cold flat rolling parameters such as effective input parameters of cold rolling, output cold rolling force and exit thickness of strips. In many mathematical models, the effect of some cold rolling parameters has been ignored and the outputs have not a desirable accuracy. In the other hand, there is a special relation among input thickness of strips, the width of the strips, cold rolling speed, mandrill tensions, required exit thickness of strips with rolling force and the real exit thickness of the rolled strip. First of all in this study, the effective parameters of cold rolling process modeled using an artificial neural network according to the optimum network achieved by using a written program in MATLAB. It has been shown that the prediction of rolling stand parameters with different properties and new dimensions attained from prior rolled strips by an artificial neural network is applicable.
    Keywords: Cold rolling, Artificial Neural Networks, rolling force, real rolled, thickness of strips
  • Mohammad Hossein Shahsavari, Farshid Ahmadi Pages 61-78
    Nowadays, equal channel angular pressing, known as the ECAP process, is one of the most popular methods for manufacturing ultra-fine grained (UFG) materials. In this paper, Ecap process has been carried out on pure copper and 6012 aluminum alloy up to six passes by route . Principal attention was paid to the influence of parameters such as diameter, material, and the height of billet on mechanical properties and hardness homogeneity induced by the process. Moreover, microhardness measurements carried out on the cross-section of the ECAPed copper and aluminum showed 103 and 46 % increase in hardness magnitude and 115 and 50% in after the sixth pass. Furthermore, hardness distribution got better for AA6012 and worse for copper after six passes of ECAP. Finally, a computer program was used to obtain effective strain distribution imposed to across the width at the center of the samples after one pass. The results obtained from the 3D FEM method were compared with the hardness measurement and showed good conformity with experimental results, which indicated that homogeneity strain improves as increasing the diameter and height had no conspicuous effect on value and homogeneity of strain and hardness of the central region of specimens.
    Keywords: ECAP, Aluminum alloy, Pure Copper, 3D FEM, strain homogeneity
  • Afshin Naeimi, Mohsen Loh Mousavi, Ali Eftekhari Pages 79-69
    In a closed die forging process, it is impossible to form complex shapes in one stage, and thus it becomes necessary to use preform dies. In the present study, Backward Deformation Method and FE simulation via ABAQUS software has been used in order to design preform die of the H-shaped parts. In the Backward Deformation Method, the final shape of the part is considered as a starting point and using a specific method, a plastic returning path is predicted. Afterwards, using FE results obtained by simulation of the forging process, an artificial neural network is designed to predict the material behavior under various conditions and for different kinds of preform to select optimum preform dies.
    Keywords: Forging Preform Die, Backward Deformation Method, ABAQUS, Artificial Neural Network