R-curve modeling for Ni/Al2O3 laminates

A metal/ceramic laminate has increased fracture toughness as compared to the ceramic monoliths. The toughness enhancement is controlled by the closure (‘bridging-stresses’) exerted by the metallic bridging layers (‘ligaments’) astride the crack in the ceramic layers. The crack-opening-displacement (COD) carries information on the level and location of these stresses. If the COD profile is known, the bridging-stresses and consequently, the R-curve behavior of the composite can be modeled. In this study, a weight-function-based approach is used to generate the R-curve and is compared with experimental results for Al2O3/Ni multilayer laminates.