Advisor(s)
Abstract(s)
One of the main approaches to increase the tool lifetime during dry machining of “hard-to-machine” aerospace
alloys is self-lubrication by the incorporation of noble metals in hard matrixes with good mechanical and
diffusion barrier properties. In this paper, the diffusion of an Ag-rich layer sandwiched between two layers of
either TiN or TiSiN is studied by transmission electron microscopy and in situ Rutherford backscattering spectrometry.
The layer stacks were subjected to annealing treatments at 600 ◦C and 800 ◦C for 2 hours. Three
processes were found to control the diffusion of silver: the morphology of the “sandwich” layers, the formation of
small voids in the involved interfaces and the sublimation of Ag in the surface at temperatures near the melting
point. The study revealed that the dense TiSiN matrix allowed a significantly better control of Ag diffusion than
the more open TiN matrix.
Description
Keywords
TiN and TiSiN layer stacks Ag diffusion, Structure Morphology
Citation
Publisher
Elsevier B.V.