A convenient method for the strength evaluation of cracked functionally graded material plates under different loadings

R Li,B Liang,S Bai,M Yang

doi:10.1063/5.0041951

Abstract

As functionally graded material (FGM) plates are widely used in engineering and industrial fields, the fracture strength evaluation of the cracked FGM plate becomes increasingly important. However, due to the gradation of the mechanical properties of FGM, few analytical methods are simple and available. In this paper, a convenient strength evaluation method for the cracked FGM plates under different loadings is proposed in terms of the stress intensity factor (SIF) appearing at a crack tip. This method uses the stable relationship of singular stress fields between FGM and homogeneous material to greatly simplify the complex SIF calculation process of the cracked FGM plate. The results show that the SIFs of FGM plates under tension, bending, and three-point bending (experiment) can be obtained conveniently and accurately by using two simple formulas, and the trends of critical SIF can also be investigated directly even if the SIF solution of the homogeneous plate (reference problem) is unknown. Comparisons with the published theoretical and experimental results indicated that the present method is reliable, precise, and practical to determine SIF and perform strength prediction.

Highlights

Graded material (FGM) plate is an advanced composite material plate with continuously changing material properties, and its material property can be designed by varying material combination and volume fraction gradient.1,2 With the extensive use of the Functionally graded material (FGM) plate in harsh and extreme environments, the fracture strength evaluation of the FGM plate has become more and more important
Many researchers have been focused on the characteristics of material gradient,3 crack form,4 and singular stress field at a crack tip to explore the fracture strength of the cracked FGM plate
A convenient strength evaluation method for the three kinds of cracked FGM plates is presented in terms of stress intensity factor (SIF)

Summary

Introduction

Graded material (FGM) plate is an advanced composite material plate with continuously changing material properties, and its material property can be designed by varying material combination and volume fraction gradient. With the extensive use of the FGM plate in harsh and extreme environments, the fracture strength evaluation of the FGM plate has become more and more important. Graded material (FGM) plate is an advanced composite material plate with continuously changing material properties, and its material property can be designed by varying material combination and volume fraction gradient.. With the extensive use of the FGM plate in harsh and extreme environments, the fracture strength evaluation of the FGM plate has become more and more important. Many researchers have been focused on the characteristics of material gradient, crack form, and singular stress field at a crack tip to explore the fracture strength of the cracked FGM plate.. Eshraghi and Soltani described the SIFs for the cracked FGM cylinders using the weight function method. As the experiment is time-consuming, the finite element analysis of the cracked FGM structure is sometimes preferred. In Ref. 11, the SIF in FGM panels is studied by using the extended finite element method (XFEM)

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Conclusion