نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشیار، مهندسی مکانیک، دانشگاه تهران، تهران، ایران

2 کارشناس ارشد مهندسی هوافضا، دانشگاه تهران، تهران، ایران

چکیده

در چند دهه‏ی اخیر کامپوزیت‌های پایه پلیمری به‌دلیل داشتن خواص فوق‏العاده از محبوبیت فراوانی برخوردار بوده‏اند. با وجود این موضوع، پلیمرها در دماهای پایین، حتی در دمای محیط دچار خزش می‏شوند که معمولاً پدیده‏ای نامطلوب محسوب می‌شود.‌ به‌منظور پیش‏بینی خزش و در نظر گرفتن اثرات آن تا کنون روش‌های متعددی پیشنهاد شده ‌است. در این مطالعه بعد از اشاره‏ای به مفاهیم خزش در پلیمرها و دسته‏بندی روش‌های پیش‏بینی خزش کامپوزیت‌های پایه پلیمری، به توسعه روشی برای پیش‌بینی خزش بلند مدت در کامپوزیت‌های پلیمری چند لایه حاوی الیاف بلند با تکیه بر داده‌های آزمایشگاهی آزمون خزش کوتاه مدت روی رزین خالص پرداخته می‌شود. مدل مورد اشاره، تنها نیازمند مشخصه سازی رفتار ویسکوالاستیک کوتاه مدت رزین بوده، پس از مدل‌سازی خزش در سطح رزین، به مدل‌سازی خزش در سطح تک لایه کامپوزیت پرداخته، در نهایت نتایج را به چندلایه کامپوزیت با آرایش دلخواه تعمیم می‌دهد. همچنین امکان استفاده از روابط مایکرومکانیک برای تخمین رفتار ویسکوالاستیک کامپوزیت بر اساس رفتار رزین و الیاف سازنده چندلایه کامپوزیت بررسی می‌شود. مقایسه نتایج حاصل از مدل‌سازی تئوری خزش بلند مدت با مشاهدات آزمایشگاهی انجام شده توسط دیگران و تطابق خوب نتایج،‌ حاکی از کارآیی مناسب مدل توسعه داده شده می‌باشد.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Modeling creep in long fiber reinforced laminated composites using micromechanical rules

نویسندگان [English]

  • Roham Rafiee 1
  • Behzad Mazhari 2

1 Faculty of New Sciences and Technologies, University of Tehran, Tehran, Iran

2 Faculty of New Sciences and Technologies, University of Tehran, Tehran, Iran

چکیده [English]

In recent decades polymeric composites have received considerable attention from different industrial sectors due to their outstanding properties. Despite the multi-purpose properties, polymers undergo creep even at room temperature which is considered as a disadvantage for their long-term applications. Numerous methods have been suggested by researchers in order to predict creep in polymeric composites. In this article, a brief review is conducted on fundaments of creep in polymers and different theoretical methods presented for creep modeling in long fiber reinforced laminated composites are categorized. Then, a new method for evaluating long-term creep in polymeric composites relying on short-term experimental data on pure resin is developed. The developed model is just in need of simple tension-creep tests on pure resin as input and creep behavior of pure resin is evaluated accordingly. Then, the results are used to estimate creep behavior a single composite laminate and finally creep behavior of laminated composites with arbitrary lay-up configurations is theoretically characterized. In parallel, the capability of micromechanical rules in estimating creep behavior of composites using its constituent’s behavior is investigated. A comparison between published experimental observations and theoretically obtained results imply on proper performance of developed modeling procedure for analyzing creep phenomenon in polymeric composites.

کلیدواژه‌ها [English]

  • Creep modeling
  • Long fiber laminated composites
  • Micromechanics
  • Viscoelastic behavior
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