Method of forming a ceramic coating on a substrate by electron-beam physical vapor deposition

摘要

A composite target is placed in a chamber. The target is in the form of a bar made of ceramic powder and it presents composition that is not uniform in the longitudinal direction. At least one substrate is introduced into the chamber in order to have formed thereon a ceramic coating with a composition gradient. The top face of the bar is swept by an electron beam so as to melt the bar material at its top face and form a vapor cloud in the chamber under low pressure. A bar is used that presents a plurality of superposed layers of different compositions, with the composition within each layer being uniform over the entire cross-section of the bar. Each layer of the bar comprises zirconia and at least one oxide selected from the oxides of nickel, cobalt, iron, yttrium, hafnium, cerium, lanthanum, tantalum, niobium, scandium, samarium, gadolinium, dysprosium, ytterbium, and aluminum.