High-resolution transmission electron microscopy investigations of a highly adhesive hydroxyapatite coating/titanium interface fabricated by ion-beam-assisted deposition.

An atomic intermixing layer, 25 nm in width, has been identified by high-resolution transmission electron microscopy (HRTEM) and energy-dispersive X-ray spectroscopy (EDS) analysis at the ceramic/metal interface of a hydroxyapatite (HA) coating/titanium implant prepared by an ion-beam-assisted deposition (IBAD) technique and post-heat-treatment process. The detailed interfacial microstructure revealed a gradient evolution of both the structure and composition of the interfacial phases from the titanium substrate to HA coatings. An enhancement of the tensile bond strength was found and was attributed to the possible chemical bonding at the ceramic/metal interface. Copyright 2000 John Wiley & Sons, Inc.