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

[1]    Leake, J., "Atomic Scale Structure of Materials", http://www.doitpoms.ac.uk/tlplib/atomic-scale-tructure/printall.php, Available in 10, May 2014.

[2]    Zabulionis, D. and Gailius, A., "Numerical Modeling Of Creep Functions Of Laminated Composites", MECHANIKA, Vol. 65, No. 3, pp. 5-10, 2007.

[3]    Silva, De., "A Theoretical Analysis of Creep in Fibre Reinforced Composites" , Department of Metallurgy, University of Cambridge ,1968

[4]    Norton, F.H., “The Creep of Steel at High Temperature”, NewYork, McGraw Hill, 1929.

[5]    Findley, W.N., “Mechanism And Mechanics Of Creep Of Plastics”, SPEJ, Vol. 16, pp. 57–65, 1960.

[6]    Tuttle, M.E. and Brinson, H.F., “Prediction Of The Long-Term Creep Compliance Of General Composite Laminates”, Experimental Mechanics, Vol. 26, No. 1, pp. 89–102, 1986.

[7]    Guedes, R.M., “Nonlinear Viscoelastic Analysis Of Thich-Walled Cylindrical Composite Pipes”, International Journal of Mechanical Sciences Vol. 52, pp. 1064–1073, 2010.

[8]    Findley, W.N., Lai, J.S. and Onaran, K., “Creep And Relaxation On Nonlinear Viscoelastic Materials”, Dover Publications, New York, 1989.

[9]    Schapery, R.A., “Theory Of Mechanical Behaviour Of Elastic Media With Growing Damage And Other Changes In Structure”, Journal of Mechanics and Physics of Solids, Vol. 38, No. 2, pp. 215-253, 1990.

[10]  Schapery, R.A., “On The Characterization Of Nonlinear Viscoelastic Materials”, Polymer Engineering and Science, Vol. 9, No. 4, pp. 295–310, 1969.

[11]  Guedes, R.M, Marques, A.T., Cardon, A.H., “Analytical And Experimental Evaluation Of Nonlinear Viscoelastic–Viscoplastic Composite Laminates Under Creep, Creep-Recovery, Relaxation And Ramp Loading”, Mechanics of Time-Dependent Materials, Vol. 2, pp. 113–28, 1998.

[12]  Farshad, M., ”Two New Criteria For The Service Life Prediction Of Plastics Pipes”, Polymer Testing, Vol. 23, pp. 967–972, 2004.

[13]  Faria, H. and Guedes, R.M., “Long-Term Behaviour Of GFRP Pipes: Reducing The Prediction Test Duration”, Polymer Testing, Vol. 29, pp. 337–345, 2010.

[14]  Kelly, P., "Solid Mechanics Part I", University of Auckland, U.S, pp. 242-254, 2014.

[15]  Wen, Y.F. Gibson, R.F. and Sullivan, J.L., “Prediction Of Momentary Transverse Creep Behavior Of Thermoplastic PMC Composites Using Micromechanical Models”, Journal of Composite Materials, Vol. 31, No. 21, pp. 2124-2145, 1997.

[16]  Xu, Y., “Creep Behavior Of Natural Fiber Reinforced Polymer Composites”, PhD Thesis, The School of Renewable Natural Resources, Louisiana State University, USA, December, 2009.

[17]   Nunez, A.J. Marcovich, N.E. and Aranguren, M.I., “Analysis Of The Creep Behavior Of Polypropylene-Wood Flour Composites”, Polymer Engineering and Science, Vol. 44, pp. 1594-1603, 1986.

[18]  Plaseied, A. and Fatemi, A., “Tensile Creep And Deformation Modeling Of Vinylester Polymer And Its Nanocomposite”, Journal of Reinforced Plastics and Composites, Vol. 28, No. 14, pp. 1775-1788, 2004.

[19]  Acha, B.A. Reboredo, M.M. and Marcovich, N.E., “Creep And Dynamic Mechanical Behavior Of PP-Jute Composites: Effect Of The Interfacial Adhesion”, Composites: Part A, Vol. 38, pp. 1507–1516, 2007.

[20]  Lou, Y.C. and Schapery, R.A., “Viscoelastic Characterization Of A Nonlinear Fiber-Reinforced Plastic”, Journal of Composite Materials, Vol. 5, No. 2, pp. 208-234, 1971.

[21]  Hadid, M. Rechak, S. and Zouani, A., “Empirical Nonlinear Viscoelastic Model For Injection Molded Thermoplastic Composites”, Polymer Composites, Vol. 23, No. 5, pp. 771-778, 2002.

[22]  Mahdi, M., “Investigation Of Mechanical Properties Of Short Fiber Composites In Elastic Form And Steady State Creep”, PhD Thesis, Sharif University, Iran, 2008.

[23]  Nunez, A.J. Marcovich, N.E. and Aranguren, M.I., “Analysis Of The Creep Behavior Of Polypropylene-Woodflour Composites”, Polymer Engineering and Science, Vol. 44, No. 8, pp. 1594-1603, 2004.

[24]  Mondali, M. Monfared, V. and Aberdian, A., “Non-Linear Creep Modeling Of Short-Fiber Composites Using Hermite Polynominals, Hyperbolic Trigonometirc Functions And Power Series”, Comptes Rendus Mecanique, Vol. 341, No. 7, pp. 592-604, 2013.

[25]  Brinson, H.F. Morris, D.H. and Yeow, Y.T., “A New Experimental Method For The Accelerated Characterization And Prediction Of The Failure Of Polymer-Based Composite Laminates”, Proceedings of the 6th International Conference for Experimental Stress Analysis, VDI-Berichte Nr. 313, pp. 395-400, West Germany, Sept. 1978.

[26]  Morris, D.H. Brinson, H.F. and Yeow, Y.T., “The Viscoelastic Behavior Of The Principle Compliance Matrix Of A Unidirectional Graphite/Epoxy Composite”, Polymer Composites, Vol. 1, No. 1, pp. 32-36, 1980.

[27]  Brinson, H.F. and Dillard, D.A., “The Prediction Of Long Term Viscoelastic Properties Of Fiber Reinforced Plastics”, Progress in Science and Engineering of Composites, (T. Hayashi, et al., Ed's), JSCM, ICCM IV, Vol. 1, pp. 795-802, 1982.

[28]  Hiel, C. Cardon, A.H. and Brinson, H.F., “The Nonlinear Viscoelastic Response Of Resin Matrix Composite Laminates”, Report No. NASA CR-3772, 1984.

[29]  Mui, J., “Viscoelastic-Viscoplastic Model To Predict Creep In A Random Chopped Mat Thermoplastic Composite”, MSc thesis, Waterloo, Ontario, Canada, 2008.

[30]  Xia, M. Takayanagi, H. and Kemmochi, K., “Analysis Of Multi-Layered Filament-Wound Composite Pipes Under Internal Pressure”, Composite Structures, Vol. 53, pp. 483-491, 2001.

[31]  Tajvidi, M. Falk, R.H. and Hermanson, J.C., “Time–Temperature Superposition Principle Applied To A Kenaf-Fiber/High-Density Polyethylene Composite.”, Journal of Applied Polymer Science, Vol. 97, pp. 1995–2004, 2005.

[32]  Dillard, D.A., “Creep And Creep Rupture Of Laminated Graphite/Epoxy Composites”, PhD Thesis, Va. Tech, USA, March 1981.

[33]  Gramoll, K.C. Dillard, D.A. and Brinson, H.F., “A Stable Numerical Solution Method For In-Plane Loading Of Nonlinear Viscoelastic Laminated Orthotropic Materials”, Composite Structures , Vol. 13, No. 4, pp. 251-274, 1981.

[34]  Chamis, C.C., “Mechanics Of Composite Materials-Past, Present And Future”, NASA Technical Memorandum,1989.

[35]  Griffith, W.I. Morris, D.H. and Brinson, H.F., “The Accelerated Characterization Of Viscoelastic Composite Materials”, Report No. NASA CR-166333, 1980.

[36]  Standard Test Methods For Tensile, Compressive, And FlexuralCreep And Creep-Rupture Of Plastics. ASTM D2990-01. American Society for Testing andMaterials; 2001.