Dynamic stress intensity factors of multiple cracks in an orthotropic strip with FGM coating

• Dynamic fracture analysis of cracked coating substrate layers is investigated.
• Non-homogeneous orthotropic layer is used.
• The excitation frequency has a significant effect on DSIF of cracks.
• The analysis can be applied for any number of cracks with arbitrary arrangements.

The problem of determining the dynamic stress intensity factors (DSIFs) in an orthotropic strip with functionally graded materials coating weakened by multiple arbitrary cracks under time-harmonic excitation are investigated. Using Fourier transform, the problem is to the solution of integral equations of the Cauchy singular type. The integral equations were solved by Erdogan’s collocation method and dynamic stress intensity factors were obtained. The proposed method of solution permits an examination of the multiple curved cracks problem with arbitrary patterns. Several examples are solved to obtain the dynamic stress intensity factors with various angular frequency, crack lengths and material properties. A knowledge of dynamic stress intensity factor is essential to the clear understanding of the propagation of cracks through structural components undergoing oscillation.