Analysis of brazed single-lap joints using the peridynamics theory

Design requirements for high-temperature applications can be usually satisfied by C/C and C/C-SiC materials. The strength of the brazed joint is controlled by increasing the thickness of the braze layer. The thickness of the braze layer is on the order of the micro scale, and the mismatch in material properties among the adherends and braze is a major source of high stress concentrations. Such stresses lead to interlayer delamination and cracking, which can lead to premature failure. The focus of this study is to analyze the effect of material properties, the braze layer, and joint geometry on the crack initiation and growth in the joint. Because the joint has macro- and micro-length scale components, its analysis requires the use of a theory at the meso-scale that accounts for the interaction of these length scales. The peridynamics theory permits time-dependent analysis at multiple length scales, damage is part of the constitutive model, and the material response is determined at the bond level. This feature allows initiation and propagation of failures inside the material without resorting to crack initiation or growth criteria.