فهرست مطالب بهروز زارع

One of the main concerns of political systems which is highly emphasized is the rights of the nation, which in fact, all countries are trying to make it the headpiece of their constitution. In the third chapter of the Constitution of the Islamic Republic of Iran, as the highest legal document of the country, this central issue of the political system has been emphasized far from extremism. In general, the rights of the nation authorized in the third chapter can be studied in the three axes of equality, security and freedom. Given the importance of the issue, in this article we will explain and examine the rights of the nation in the constitution and we will explore the existing guarantees of implementation. In general, the purpose of this article is to inform all members of society about their rights and duties and the guarantees of implementation in this field. The method of conducting this research is descriptive-analytical and the result of the research indicates that according to the Constitution of the Islamic Republic of Iran, all members of the society are equal, and that the equality of rights and duties and the implementation of these rights will not be possible without a guarantee of implementation.

Multi-Point forming process is a flexible technique for manufacturing of various sheet metal parts. In this paper, Multi-Point forming technique is studied using FE simulation and experiments. In order to estimate proper design parameters, the forming process was initially simulated dynamically, and then the Multi-Point forming die set was built for conducting experimental tests. By considering the widespread usage of aluminum alloys in the field of aerospace, the AA2024 aluminum alloy is used in this research and forming of sheet parts under various forming conditions is examined. The failure modes are predicted and the effect of process parameters such as pin diameter and thickness of elastic cushion on the geometry accuracy and thickness distribution of formed parts are investigated.The results obtained show that this process can be used as an effective and economic method for producing small batch production in different industrial sectors particularly aerospace industry. By proper adjustment of process parameters, the production of parts with different geometry will be possible just by using one same die set.

The aim of this paper is to develop a systematic method to analyze the effects of forming parameters on the quality of part formability and determine the optimal combination of the forming parameters for the sheet hydroforming process. In this paper، the effects of four important process parameters namely fluid pressure، friction coefficient at blank/punch interface، gap between die rim block and blank holder and die entrance radius in the process of hydrodynamic deep drawing assisted by radial pressure (HDDRP) were determined. A Finite Element (FE) model was developed for simulating the HDDRP process. After validation of the developed FE model by experimental results، by combining FE simulation with Taguchi method and using the analysis of variance test، the effect of mentioned parameters on the formability of the hydroformed cups was investigated. The applied materials were pure copper and St14 steel sheets. The results of analysis indicated that for both cases of maximum thinning ratio at the constant value of cup draw depth and maximum accessible draw depth، fluid pressure has the greatest influence on the formability of part in sheet hydroforming process. Moreover، using rough punch، having smaller gap between die rim block and blank holder or increasing the die entrance radius، the formability of sheet will improve.

In recent years, in order to reducing die design and manufacturing costs, Multi point forming technique has gained an increasing interest because of its high flexibility. In this process, the conventional fixed shape solid die sets are replaced with a pair of opposite matrices of controllable elements. In this paper, the fundamental principles of multi-point forming was described and the possibility of forming the one sheet metal part by this technique was investigated experimentally and analyzed using finite element simulation. Wrinkles and dimples are the most typical defects in multi-point forming of sheet metal. By the proper selection of process parameters the sound cup with good surface quality and uniform thickness distribution can be formed. The results obtained demonstrated that multi-point forming technology can be used as an effective and economic tool to the forming of single parts with different shapes and is cost-effective.

Due to the bad cold-formability of aluminum alloys in deep drawing process، many forming methods have been explored to increase the drawing ratio of these alloys. Sheet Hydro-Forming is one of the processes that can be used to the forming of cups with high drawing ratio from bad cold-formability materials. In this paper، the forming of AA6063-T4 aluminum alloy hemispherical-cylindrical cups by hydrodynamic deep drawing assisted by radial pressure were investigated experimentally and analyzed using finite element simulation. By examining several pressure paths، the effect of pressure path on bursting and thickness distribution of the sheet was studied. The results indicated that by using this process and applying an appropriate pressure path، the sound cups، with high drawing ratio and uniform thickness distribution could be formed in one stage. Also، in this paper by using FE simulation and Taguchi technique، a systematically method was developed to analyze the effects of the forming parameters on the quality of part formability and determine the optimal combination of the forming parameters for sheet Hydro-Forming process. The results of analysis indicated that fluid pressure has the greatest influence on the part formability in sheet Hydro-Forming process. And also by using rough punch، lower gap between die rim block and blank holder and greater die entrance radius the formability of sheet will be improved.