Nanoporosity improves the damage tolerance of nanostructured tantalum nitride coatings
School of Engineering
Conventionally, nanostructured ceramics are susceptible to brittle fracture due to processing-induced flaws such as porosity. In this study, the microstructure and deformation behavior of two nanostructured Ta2N coatings, one with a fully-dense structure and the other with a nanoporous structure, both prepared by double cathode glow discharge technique, were investigated. It was found that the elastic modulus of the Ta2N coatings is more sensitive to the presence of nanoporosity than their hardnesses. Compared with the fully-dense Ta2N coating, the nanoporous Ta2N coating exhibits a marked increase in the damage tolerance, as well as a good potential for wear-resistance.