نوع مقاله : مقاله پژوهشی

نویسندگان

1 کارشناس ارشد ، مهندسی مکانیک ، دانشگاه تهران، تهرا ن

2 دانشیار ، مهندسی مکانیک ، دانشگاه تهران، تهرا ن

3 استادیار ، مهندسی مکانیک ، دانشگاه تهران، تهرا ن.

چکیده

برای جلوگیری صدمات ناشی از خستگی در تجهیزات و سازه‌های ترک‌خورده، ترمیم به عنوان راهکاری مناسب شناخته شده است. از بهترین روش‌ها برای ترمیم قطعات ترک خورده، استفاده از کامپوزیت‌های پلیمری و اتصال با استفاده از چسب می‌باشد. در این مقاله به بررسی اثر کیفیت سطح در عمر خستگی قطعات ترمیم شده با وصله کامپوزیتی پرداخته می‌شود. صفحه ترک خورده از آلومینیوم 1050 با ترک لبه‌ای می‌باشد و ترمیم مورد استفاده به صورت یک طرفه بوده است. از الیاف شیشه حصیری شکل به عنوان وصله و از چسب آرالدیت برای اتصال وصله به قطعه ترک خورده استفاده شده است. نتایج آزمایش تجربی نشان می‌دهد که ایجاد زبری کم با استفاده از کاغذ سنباده 600 می‌تواند باعث افزایش عمر % 7 در قطعات ترمیمی شود. اما با افزایش مقدار زبری از این مقدار، عمر قطعات از حالت پایه (حالت زبر نشده) کمتر می‌گردد؛ تا جایی که قطعات زبر شده با کاغذ سنباده 40 منجر به کاهش عمر در حدود % 25 می‌گردد.

کلیدواژه‌ها

عنوان مقاله [English]

Experimental investigation of surface finishing in cracked aluminum plates reinforced by composite patch under fatigue loading

نویسندگان [English]

  • Mahdi Najafpour Mollabashi 1
  • Majid Safarabadi 2
  • Mojtaba Haghighi Yazdi 3

1 School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran

2 School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran.

3 School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran.

چکیده [English]

To prevent fatigue damages in cracked equipment and structures, the repair is known as a proper method. One of the best practices for repairing cracked plates is using polymer composites with adhesive bonding joints. In this paper, the effects of surface finishing on fatigue life of repaired plates with the composite patch were investigated. The single edge cracked plate was made of aluminum 1050 and the repair was applied for one side of the plate. The woven fiberglass was used as a patch and it was jointed to the cracked plate by Araldite adhesive. In this case, the roughened surface by sandpaper No.40 increased the plate properties by 55%. Also, the experimental results revealed that making low roughness on the cracked plate using sandpaper No.600 increases the life cycles by 7%. However, a higher value of roughness reduced the life cycles of repaired plates compared to the base case (plates without roughness) up to 25%.

کلیدواژه‌ها [English]

  • Composite patch
  • Fatigue crack propagation
  • Roughness
  • Cohesive joint
  • Stress intensity factor
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