Determining the mixed mode stress intensity factors of surface cracks in functionally graded hollow cylinders

This work reports about an investigation on mixed mode stress intensity factors (SIFs) of three-dimensional (3D) surface cracks in hollow cylinders made-up of functionally graded material (FGM). A finite element implementation of the interaction energy integral in domain form is employed to extract the SIFs. In turn, surface cracks located at the inner and outer wall of the cylinders are considered, and the influence of exponentially varying Poisson’s ratio and Young’s modulus in radial direction on the SIFs is studied in detail. The computational results reported herein show that graded materials properties can significantly affect the magnitude and the distribution of SIFs along 3D crack fronts in FGM hollow cylinders.

► The SIFs of surface cracks in FGMs hollow cylinders were determined. ► A FE procedure based on the interaction energy integral was employed. ► The influence of graded Young’s modulus and Poisson’s ratio was explored. ► Distribution of SIFs along 3D crack fronts in FGM cylinders was established. ► The results can be used to assess the integrity of cracked hollow FGM cylinders.