Investigation of the Near-Tip Stress Field of a Notch Terminating at a Bi-Material Interface.

Grzegorz Mieczkowski,Ahmed Elgarayhi,Andrzej Borawski,Mohamed M Awad,Dariusz Szpica,Mohammed Sallah

doi:10.3390/ma14164466

Grzegorz Mieczkowski, Ahmed Elgarayhi + Show 4 more

Open Access

https://doi.org/10.3390/ma14164466

Copy DOI

Abstract

The article deals with the problem of a sharp corner, the tip of which is located on the bi-material interface. The paper presents a qualitative and quantitative description of singular stress fields occurring in the tip area of such a stress concentrator. The qualitative description was obtained by solving the problem of the plane theory of elasticity with appropriately defined boundary conditions. To obtain a quantitative description, it was necessary to determine the values of generalised stress intensity factors (GSIFs). The GSIFs were determined using the developed analytical-numerical method. The calculations were made for various load variants (uniaxial/biaxial tension load, shear load) and notch positions (single/double edge-notched plate, centre-notched plate). Additionally, the impact of notch geometry (height and opening angle) and relative stiffness (Young’s moduli ratio of both components of bi-material) on GSIFs was investigated. It has been noticed that with a decrease in the relative stiffness and an increase in the notch angle or its height, the normalised GSIFs values increased. The obtained results were compared with the data available in the literature and their satisfactory agreement with those presented by other scientists was found.

Highlights

Ensuring the high durability of the structure with minimum costs is a priority of today’s world economy
In the case where the stress concentrator is located inside only one material phase, the failure criteria commonly used for isotropic materials can be used to predict fracture [1,2,3,4]
The analytical description of the stress fields was obtained by solving (with the acThe analytical description of the stress fields was obtained by solving a plane problem of two connected elastic accuracy of multiplicative constants called generalised stress intensity factors (GSIFs)) a plane problem of two connected elastic half-spaces, the interface of which is weakened by a sharp corner (Figure 1)

Summary

Introduction

Ensuring the high durability of the structure with minimum costs is a priority of today’s world economy. The durability of the structure largely depends on the strength of the materials used for its components. Various types of composites are widely used, which, compared to traditional construction materials, are characterised by greater strength and at the same time lower specific weight. They often contain various material defects (voids, inclusions) causing the formation of local stress fields with large gradients. This results in the initiation of new cracks or the propagation of the existing ones. In the case where the stress concentrator is located inside only one material phase, the failure criteria commonly used for isotropic materials can be used to predict fracture [1,2,3,4]

Methods

Results

Conclusion