ارزیابی معیارهای رشد ترک در پلیمر مدرج تابعی به‌روش اجزای محدود

نوع مقاله : مقاله پژوهشی

نویسندگان

• مهدی نجیمی ¹
• فرهاد حاجی ابوطالبی ²
• حمید بهشتی ³

¹ دانشگاه اصفهان

² صنعتی اصفهان

³ اصفهان

10.22067/fum-mech.v28i2.49913

چکیده

در این پژوهش، ابتدا معیارهای مختلفی مانند معیار بیشینه تنش مماسی، بیشینه نرخ رهایش انرژی و کمینه چگالی انرژی کرنشی مورد ارزیابی قرار می‌گیرند. سپس با به‌کارگیری روش انتگرال تعاملی (انتگرال M) در یک پلیمر مدرج تابعی، ضرایب شدت تنش برای حالت-های مختلف جهت‌گیری ترک و خواص مکانیکی ماده محاسبه می‌گردد. بااستفاده از نتایج حاصل، زاویۀ آغاز ترک از معیارهای مختلف به‌دست آمده و با نتایج تجربی موجود در مقالات مقایسه می‌شود. نتایج آشکار می‌کند که پیش‌بینی‌های معیارهای بیشینه تنش مماسی و کمینه چگالی انرژی کرنشی به‌هم نزدیک است ولی معیار کمینه چگالی انرژی کرنشی از دقت بهتری برخوردار است. در آخر، مسیر رشد ترک محاسبه ‌شده با نتایج تجربی موجود در پژوهش‌ها مقایسه می‌گردد و دقت معیار کمینه چگالی انرژی کرنشی، نشان داده می‌شود.

کلیدواژه‌ها

• معیارهای رشد ترک
• پلیمر مدرج تابعی
• روش انتگرال تعاملی
• روش اجزای محدود

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عنوان مقاله [English]

Evaluation of Crack Growth Criteria in Functionally Graded Polymer using Finite Element Metho

نویسندگان [English]

• Mehdi Najimi ¹
• farhad haji aboutalebi ²
• Hamid Beheshti ³

¹ University of Isfahan

² Isfahan University of Technology

³ Wichita State University, USA

چکیده [English]

In this research first, different fracture criteria such as maximum tangential stress, maximum strain energy release rate, and minimum strain energy density are evaluated. Then, employing the interaction integral (M-integral) method in a functionally graded polymer, stress intensity factors for different directions of the crack orientation and mechanical properties are calculated. Applying the achieved results, the initiation angle of the crack is obtained by the various fracture criteria and compared with the experimental results existed in the papers. The results reveal that the predicted results of the maximum tangential stress and the minimum strain energy density criteria are close to each other but, the minimum strain energy density criterion has better accuracy. Finally, the calculated crack growth path is compared with the experimental results existed in the researches and the accuracy of the minimum strain energy density criterion is shown..

کلیدواژه‌ها [English]

• Crack Growth Criteria
• Functionally Graded Polymer
• Interaction Integral Method
• Finite Element Method

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