فهرست مقالات Polycarbonate

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  1 - The Effect of Power and Maximum Cutting Speed on the Material Removal Rate and Cutting Volume Efficiency in CO2 Laser Cutting of Polycarbonate Sheets
  Majid Hashemzadeh Mehdi Mahammadi
  In the laser cutting process some well-known parameters, e.g. laser power and cutting speed, play major roles in the performance of the process. Each parameter or a combination of parameters can affect the material removal volume and cutting volume efficiency. The purpo چکیده کامل

  In the laser cutting process some well-known parameters, e.g. laser power and cutting speed, play major roles in the performance of the process. Each parameter or a combination of parameters can affect the material removal volume and cutting volume efficiency. The purpose of this research is to study the effect of power and maximum cutting speed on the material removal rate (MRR) and cutting volume efficiency (αVol) in CO2 laser cutting of polycarbonate (PC) sheets. A CO2 laser cutting machine with a maximum power of 130 W was used to cut PC sheets with thicknesses of 2 to 8 mm. The spot size of the focused beam was 0.1 mm on the upper surface of the sheet. The cutting experiments were carried out by varying the laser power from 20 to 100 W and the maximum cutting speed was found for each power. In the range of applied laser parameters for cutting of PC sheets, the results show that the MRR increases with power. The results also indicate that the MRR increases with maximum cutting speed and thickness. The cutting volume efficiency (αVol) increases with power until it reaches the apex of efficiency then, it slightly reduces with increasing power. پرونده مقاله
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  2 - Friction Stir Welding of Dissimilar Poly Methyl Methacrylate and Polycarbonate Sheets
  Mojtaba Rezaee Hajideh Omid Shapurgan Navid Molla Ramzani Essa Hasan Nejad
  The widespread application of thermoplastic polymers in different aspects of industries has motivated researchers and companies to improve and upgrade their forming, joining and assembling processes to overcome their limitations. One of the newest joining methods of the چکیده کامل

  The widespread application of thermoplastic polymers in different aspects of industries has motivated researchers and companies to improve and upgrade their forming, joining and assembling processes to overcome their limitations. One of the newest joining methods of thermoplastics is friction stir welding which is based on frictional heat generated through contact between a rotating tool and the workpiece.The aim of this study is to investigate the weldability of dissimilarpoly methyl methacrylate and polycarbonatesheets via friction stir welding approach.The effects of process parameters such as rotational and traverse speeds and the heater temperature on the mechanical properties of the joints were studied comprehensively. Rotational and traverse speeds and heater temperature of 2100 rpm, 8 mm/min and 120 °C, offered the optimized mechanical properties of the joint. In the optimum joining condition, welded joint with strength equal to 98% of polycarbonate and with higher hardness than the polycarbonate was obtained. پرونده مقاله