بررسی استحکام برشی در جوش لبه در جوشکاری اصطکاکی اغتشاشی آلومینیوم 7075

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشکده مهندسی مکانیک، دانشگاه صنعتی امیرکبیر، تهران، ایران

2 پژوهشکده فناور یهای نو، دانشگاه صنعتی امیرکبیر، تهران، ایران

چکیده

استفاده روزافزون در صنایعی مانند هوافضا، اتومبیل و حمل و نقل، منجر به ساخت سازه ها و توسعه گستره ی تحقیقات در زمینه ساخت و تولید آلومینیوم و آلیاژهای آن شده است. از طرفی جوشکاری ذوبی آلومینیوم و آلیاژهای آن به دلیل مشکلاتی که در خصوصیات فیزیکی، حرارتی و متالورژیکی قطعه نهایی ایجاد می کند، یکی از موانع بر سر راه استفاده از آلومینیوم
می باشد. جوشکاری اصطکاکی اغتشاشی یک روش غیر ذوبی است که با تولید گرمای اصطکاکی و تغییر شکل پلاستیکی در موقعیت اتصال، مزیت هایی مانند اعوجاج پایین، فقدان عیوب مربوط به ذوب و استحکام اتصال بالا را دارا می باشد. در این مقاله، جوشکاری اصطکاکی اغتشاشی آلیاژ آلومینیوم AA7075-O در حالت لبه روی هم با هدف مطالعه استحکام برشی ناحیه جوش به روش المان محدود توسط دو نرم افزار دفرم و آباکوس به صورت متوالی شبیه سازی شده و به صورت تجربی نیز مورد بررسی قرار گرفته است. در بررسی استحکام برشی میزان اختلاف شبیه سازی با آزمون تجربی % 14 - 15 اندازه گیری شده که نشان دهنده دقت مناسب شبیه-سازی المان محدود فرآیند جوشکاری اصطکاکی اغتشاشی است. همچنین، نتایج شبیه سازی ها نشان می دهد که بیشینه تنش برشی ناحیه اتصال برابر 165Mpa است که در سرعت دورانی 1250rpm ، سرعت خطی 50mm/min و زاویه انحراف 3˚ حاصل می گردد

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Investigating the Shear Strength of Friction Stir Lap Welded 7075 Aluminum Alloy

نویسندگان [English]

  • H. Samarikhalaj 1
  • A. Nikbakht 2
  • M. Sadighi 1
  • S. Sheikhan 1
1 Department of Mechanical Engineering, Amirkabir University of Technology, Tehran, Iran
2 New Technologies Research Center, Amirkabir University of Technology, Tehran, Iran
چکیده [English]

Creating melt joints in aluminum is an obstacle in introducing this metal into structures.
This is due to the fact that fusion welding methods of aluminum leaves mechanical and metallurgical
defects in the final produced parts. Friction stir welding is a non-melting replacement fabrication method,
which creates welded joints from a semi-solid material state. In this paper, friction stir lap welding of
7075 aluminum alloy is studied both numerically and experimentally with the aim of investigating the
shear strength of the welded joint. The shear strength which is calculated by the simulation is maximum
14 to 15 % lower to the acquired experimental results, which shows that the simulation process can
appropriately be utilized to predict the shear strength of the welded joints for different cases. In addition,
the results show that the maximum shear strength is equal to 165 Mpa which is obtained for a case in
which the rotational speed is 1250 rpm, the linear speed is 50 mm/min and the tilt angle is set to 3˚.

کلیدواژه‌ها [English]

  • Friction stir lap welding
  • Finite elements method
  • Shear Strength
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