Patent ID: 6808761
Filing Date: 2004-10-26
Classification: C04B,C23C,F01D,F05D,Y10T

Abstract:
A method of forming a ceramic coating on a substrate by electron-beam physical vapor deposition, the method comprising the steps of:placing in a chamber a composite target in the form of a bar made up of ceramic powder and presenting a composition that is not uniform in the longitudinal direction; introducing into the chamber at least one substrate on which a ceramic coating having a composition gradient is to be formed; and sweeping a top face of the bar with an electron beam in order to melt the bar material at its top face and form a vapor cloud in the chamber at low pressure, wherein: a bar is used that presents at least three layers of different compositions, the composition within each layer being uniform over the entire cross-section of the bar, and each layer comprising 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; and the ceramic coating formed on the substrate by progressively consuming the bar reflects the variation in the composition of the bar.