Loading...
A Progressive Multiscale Model to Predict the Fatigue life of Laminated Composite Reinforced with Nanoparticles
Toozandehjani, Hossein | 2017
1561
Viewed
- Type of Document: Ph.D. Dissertation
- Language: Farsi
- Document No: 50263 (45)
- University: Sharif University of Technology
- Department: Aerospace Engineering
- Advisor(s): Hoseini Kordkhili, Ali
- Abstract:
- The increasing growth of composite materials in various industries and the use of these materials in the production of the main structures, recognized study and simulation of accurate behavior of these materials at different scales. On the other hand, the appearance of Nano-scale materials with amazing physical and mechanical properties and the use of these nanoparticles as reinforcement in the structure of polymer composites, further highlights the importance of simulating the behavior of polymer nanoparticles at different scales. One of the issues that is considered in various industries, especially in the airspace industry, is the phenomenon of fatigue. The complexity of the fatigue phenomena on the one hand and the multi-scale of polymer Nano-composites on the other hand require further study to provide a comprehensive multi-scale model for predicting the fatigue life of these materials. In this thesis, a multi-scale progressive micro-mechanical fatigue model is presented. The model employs fundamental equation of the kinetic theory of fracture to calculate damage parameters of both fiber and matrix during cyclic loading. In order to adapt the equation, required material coefficients of the constituents can be achieved from fatigue test results of longitudinal and transverse unidirectional Nano-composites, only. Sharing stress capacities of fiber and matrix are determined using a modified progressive micro-mechanical equivalent inclusion method in the presence of damage. The damage parameters in the constituents are calculated employing two different equivalent scalars. The enhanced formulation is then implemented into the commercial finite element software of ABAQUS via a developed user material (UMAT) subroutine utilizing a suitable failure criteria and an own solution algorithm. Advantages of the proposed model are assessed and comparisons with available solutions are presented
- Keywords:
- Fatigue ; Representative Volume Element ; Nanocomposite ; Carbon Nanotubes ; Progressive Failure Analysis ; Multiscale Method ; Fatigue Life
- محتواي کتاب
- view
- چکیده
- فهرست مطالب
- فهرست جدولها
- فهرست شکلها
- 1- فصل اول: مقدمه
- 2- فصل دوم: مرور موضوعی بر ادبیات
- 3- فصل سوم: آزمایشات تجربی
- 4- فصل چهارم: توسعه مدل میکرومکانیکی تعیین خواص
- 5- فصل پنجم: مدل میکرومکانیکی تحلیل استاتیکی کامپوزیتهای لایهای
- 6- فصل ششم: مدل خستگی چند مقیاسی برای پیشبینی عمر خستگی
- 7- فصل هفتم: نتیجهگیری و پیشنهادها
- 8- مراجع