Chemical Engineering
M. Imani-Hassanloui; M. R. Maraki; Z. Taghimalek; H. Tagimalek
Abstract
Nowadays, vending is the most important pillar of a production set. The positive and significant points of the manufactured parts are attained by interviewing with the customer, sending a questionnaire to the customer, testing the market, investigating the quality and reliability of new products, probing ...
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Nowadays, vending is the most important pillar of a production set. The positive and significant points of the manufactured parts are attained by interviewing with the customer, sending a questionnaire to the customer, testing the market, investigating the quality and reliability of new products, probing the reports and product quality of competitors. Aimed at predicting the type of leadership in reverse engineering, based on “Voice of Customer” (VOC), between the Iran Khodro Company’s (IKC) managers (case study of Peugeot 405 brake pump shell), the present study was conducted. Using descriptive-correlation research method, about 90 managers were randomly selected in several categories according to gender, age and years of service, proportional to the size of each category. Three questionnaires of “Oregon and Kanowski Organizational Citizenship Behavior” (OKOCB), “Fry Spiritual Leadership” (FSL), and researcher-made “Charismatic Leadership” (CL) were utilized to collect the research data. To measure the reliability rate using Cronbach's alpha coefficient, this item was obtained for all three questionnaires of the OKOCB, FSL and CL behavior (α = 0.92, 0.81 and 0.85) respectively. Collecting the data, they were analyzed using multiple regression analysis and based on the research hypotheses. The results indicated that there is a positive and significant relationship between the dimensions of SL and organizational citizenship behavior, and also between the CL and the organizational citizenship behavior. The results of structural equation modeling also showed that SL with a path coefficient 0.7 is able to affect overall quality management (t ≥ 1.96, p≤ 0.05).
Chemical Engineering
M. R. Maraki; H. Tagimalek; B. Pasoodeh
Abstract
The copper/aluminum composite is very important and practical due to its light weight, optimal thermal and electrical conductivity. The high weight resistance ratio, along with its inherent properties, makes it attractive for new applications. In this regard, the use of composites with high mechanical ...
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The copper/aluminum composite is very important and practical due to its light weight, optimal thermal and electrical conductivity. The high weight resistance ratio, along with its inherent properties, makes it attractive for new applications. In this regard, the use of composites with high mechanical properties has significantly increased. In this research, 5000 series aluminum and pure copper samples in 1st, 2nd, 3rd, and 4th passes have been subjected to friction stir welding (FSW) and then the mechanical and metallurgical properties of the welded samples have been compared with the original samples. In order to further study the results of tensile tests, metallography and microhardness tests have been performed. Microstructural evaluation of welded samples showed that the mixing zone of the samples was determined by combining aluminum and copper layers. The results showed an increase in yield strength in the welding zone and ultimately an improvement in hardness and ultimate strength in the weld zone compared to the prototype. Compared to stretched samples, the greater the distance from the nugget weld, the less the improvement in mechanical properties and microhardness. By changing the parameters and increasing the inlet temperature, the mixing and uniform dispersion of the particles is performed more appropriately and ultimately increases the tensile strength. Finally, in the research, experimental data were modeled using fuzzy logic method and considering that the presented model was obtained in two indices R-Sq (pred) and R-Sq (adj), 96 and 99%, respectively. The comparison between the experimental data and the model data indicated an acceptable error in the experimental data.
H. Tagimalek; M. R. Maraki; M. Mahmoodi; P. Mohammad Zadeh
Abstract
Forging is one of the oldest and the most important processes of metal forming. The process occurs due to the waxy deformation of metal. In the forging process, the die walls control the material flow and the mechanical properties of the workpiece are significantly improved. Today's world industries, ...
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Forging is one of the oldest and the most important processes of metal forming. The process occurs due to the waxy deformation of metal. In the forging process, the die walls control the material flow and the mechanical properties of the workpiece are significantly improved. Today's world industries, financing costs play a leading role in production. These categories have entered the industry to create a variety of simulation and numerical modeling methods to eliminate this problem. Simulation and experimental test, mechanical properties in the hot forging process in high-cost materials are of great interest to researchers. In this paper, the mechanical properties of hot forging in Ti6Al4V alloy are investigated. According to the obtained results, it can be found that a very close agreement has been made on experiments reported in literature and the simulation. Depending on the results, the strain rate Z-axis showed the shear bands appeared exactly on the 45-degree plates and in the sample center. In fact, the intersection of the band's sample center is the max strain applied to the die. This area has been created with an effective strain and stress at all depths of the workpiece and gradually expands.