Stress intensity factor of an anti-plane crack parallel to the weak/micro-discontinuous interface in a bi-FGM composite

Abstract

The problem considered is a mode III crack lying parallel to the interface of an exponential-type functional graded material (FGM) strip bonded to a linear-type FGM substrate with infinite thickness. By applying the Fourier integral transform, the problem was reduced as a Cauchy singular integral equation with an unknown dislocation density function. The collocation method based on Chebyshev polynomials proposed by Erdogan and Gupta was used to solve the singular integral equation numerically. With the numerical solution, the effects of the geometrical and physical parameters on the stress intensity factor (SIF) were analyzed and the following conclusions were drawn: (a) The region affected by the interface or free surface varies with the material rigidity, and higher material rigidity will lead to bigger affected region. (b) The SIF of the crack in the affected region and parallel to the micro-discontinuous interface is lower than those of the weak discontinuous cases. Reducing the weak-discontinuity of the interface will be beneficial to decrease the SIF of the interface-parallel crack in the region affected by the interface. (c) The effect of the free surface on SIF is more remarkable than that of the interface, and the latter is still more notable than that of the material rigidity. When the effects of the interface and free surface are fixed, increase of the material rigidity will enhance the value of SIF.

Impact toughness and wear resistance of different equivalent ratios of 316 L and 2Cr13 by laser melting deposition on Q235 steel

“…Many studies have suggested that 316 L stainless steel possesses impressive corrosion resistance and impact toughness [27][28][29]. Meanwhile, 2Cr13 is a widely deployed stainless steel renowned for its elevated hardness and all-encompassing performance [30,31]. The requirement for high hardness may be satisfied by blending alloy powder of 316 L and 2Cr13, and the impact toughness may be maintained through the thickness of the cladding layer.…”

Effects of the weak/micro-discontinuity of interface on the fracture behavior of a functionally graded coating with an inclined crack

“…As a result, the materials within some extent of both sides of interface might be changed as functionally graded materials, i.e., the bi-material interface becomes a bi-FGM one [13][14][15]. For the bi-FGM interface, Li et al [16][17][18] brought forth the concepts of weak/micro-discontinuity and through fracture analysis found the SIF-reduction effect of the weak/micro-discontinuity on a bi-FGM interfacial crack.…”