Calculation of stress concentration around a hole in a hybrid composite lamina using finite element method

Journal of Mechanical Research and Application

دوره 10، شماره 1، مرداد 2020، صفحه 25-34   

نویسندگان

Pezhman Taghipour Birgani^* ؛ Pedram Lorzadeh

Department of Mechanics Engineering, Islamic Azad University, Ahvaz, Iran

چکیده

The hybrid composites have exceptional properties such as strength to weight and hardness ratios. These characteristics make the application of these materials in the aerospace industry. In such industries, any defects in the form of holes or cracks will increase the tension in these materials and fail, which are very dangerous. In composite materials, there are various fittings, such as a bolt and a rivet, which is the focus of stress concentration in the joints because the fibers are damaged. In this research in hybrid composite materials, a high elastic modulus fiber (HM) and a low elastic modulus fiber (LM) are used. It is also assumed that the length of the sheet is infinite. The force on the lamina is tensile force which applies on matrix and fibers while the fibers in the layers are one directed. In this paper the effects of different parameters such as number of total fibers , number of broken fibers , the ratio of LM to HM fiber extensional stiffness , Hole dimension ratio are considered. By using finite element method (FEM) stress concentration around the hole in a hybrid composite lamina is calculated and compared by the results obtained by analytical method [1] via written codes for finite element method.In this research unlike reference the matrix can withstand tensile stress. The results of the validation showed that compared to the reference data are close to each other, indicating the correctness of the code written for the analysis.

کلیدواژه‌ها

Hybrid composites؛ Lamina؛ Hole؛ Finite element method؛ Stress concentration