Delamination cracks in multilayered circular shafts loaded in torsion are analyzed in terms of the strain energy release rate. It is assumed that the material in each layer has non-linear mechanical behaviour that is treated by the Ramberg-Osgood constitutive law. Also. each layer exhibits smooth material inhomogeneity in radial direction. https://danddcollectiblers.shop/product-category/ornament/