Evaluation of energy release rate for circular coated inclusion under uniaxial tension by M-integral method = 단축인장하에 있는 원형 코팅의 에너지해방율에 대한 M 적분법에 의한 해석 연구

다국어 초록 (Multilingual Abstract)

Materials used for various applications are inherently inhomogeneous though we consider it homogeneous and isotropic for simplicity of analysis. Composite materials which are very common now a days for various applications in both large and small structures are designed in such a way that it has different layers and these layers have different material properties gives rise to the material inhomogeneity at the interfaces of these layers. Material inhomogeneity can cause stress concentration. Energy can be released or absorbed depending upon the elastic modulus mismatch between interfacing layers. The stress concentration along with energy release rate (GC) when reaches at its critical value can contribute to material failure. We have presented analytical solution for M-integral, the measure of energy release rate for self similar expansion in fiber, coating and matrix and studied the effect of material inhomogeneity by choosing different shear modulus ratio of fiber - matrix and coating ? matrix. The effect of coating thickness on energy release rate is also studied. It has been found that combination of stiffer fiber and softer coating in comparison to matrix absorbs energy while when fiber becomes softer and coating becomes stiffer with respect to matrix, it releases energy. Thickness of coating also have significant effect on energy release or absorb rate as in case of thicker coating, the energy release/absorb rate is smaller in both coating and matrix region while it increases significantly when we choose thinner coating. This study will be very helpful for understanding the energy release/absorb due to material inhomogeneity and coating thickness and thus help to understand the critical region of failures in such structures which can contribute for design improvements for composite structures with inclusions.

목차 (Table of Contents)

• ABSTRACT
• 1. Introduction
• Expression of M-Integral
• Results and Discussions
• Energy Release/ Absorb rate in Matrix region
• Energy Release/Absorb Rate in Coating Region
• Conclusion
• References