|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Fracture Properties and Residual Stresses in Small Dimensions
||In Situ Stable Fracture of Sapphire-Niobium Interfaces
||Rui Hao, Giorgio Sernicola, Eduardo Saiz, Finn Giuliani
|On-Site Speaker (Planned)
There are many interesting mechanical properties that can be achieved with metal/ceramic multilayers. However, the deformation or fracture mechanisms can be complex. To simplify the problem, in this work we have concentrated on the effect of a single metal interlayer (30-200 nm thick) within a ceramic bi-crystal. The samples were produced by sputtering niobium on to sapphire substrates and then diffusion bonding the two coated crystals together. These were then orientated so the interface was vertical and a series of micropillars containing the niobium interlayer were cut. These were then loaded under displacement control with a wedge to form a double cantilever beam geometry in situ within an SEM. This allowed the evolution fracture energy with crack length along the interface to be calculated. The correlation of the fracture energy to the microstructure and thickness of the interface will then be discussed.