Level Set function-based Functionally Graded Material for the reduction of maximum stresses around a pair of inclined unequal circular holes

Abstract

OBJECTIVE: The aim of this work is to present the methodology for grading the Functionally Graded Material (FGM) using Level Set (LS) sign distance function around the multiple holes and parametrically analyse the maximum stresses for a pair of inclined unequal circular holes surrounded by the FGM layer in an infinite plate subjected to uniaxial tensile load using the Extended Finite Element Method (XFEM). METHODS: The LS method has the ability to represent the multiple geometrical boundaries with a single sign distance function which can be effectively used for grading the FGM around the multiple discontinuities such as holes, inclusions, cracks, etc. When dealing with FGM material grading around multiple discontinuities, it is important to have smooth grading to minimise the stress concentration. The grading of the material with multiple functions may result in sharp changes in the material properties at the interference region which may lead to high stresses. The LS function-based FGM material grading eliminates such sharp changes as it uses a single function. RESULTS: The parametric analysis shows that applying the LS function-based power law FGM layer of Titanium – Titanium Mono Boride (Ti-TiB) around the pair of inclined unequal circular holes significantly reduces the values of maximum tensile as well as compressive hoop stresses when compared with the homogeneous material case.

Modeling and Stress Analysis of Rounded Rectangular Inclusion Enclosed by FGM Layer

“…FGM layer around the discontinuity is one of the approaches which can reduce property mismatch and avoid stress concentration. FGM is a composite material concept consisting of varying volume fractions of its constituents that result in smooth variation in material properties along the direction of gradation (Goyat et al, 2021). Luo and Gao (2009) solved the stress analysis problem of arbitrary inclusion using complex variable method and Faber-Laurent series.…”

On stress concentration analysis of inverse distance weighted function based finite FGM panel with circular hole under biaxial loading

“…Yang et al (2021) experimentally investigated the stress concentration reduction for a circular hole with FGM layer and observed that the experimental results have good agreement with theoretical results. Goyat et al (2021) analyzed the SCF reduction and optimized the parameters of level set based FGM for inclined pair of circular holes.…”