Al—Cr-based ceramic coatings with increased thermal stability

A turbine component coated with a coating comprising a multilayer film, comprising aluminum, chromium, oxygen and nitrogen, produced by a method for producing a multilayer film in a vacuum coating chamber, the multilayer film comprising individual layers of type A and individual layers of type B deposited alternate one of each other forming a multilayered structure with sequence of individual layers B/A/B/A/B/A . . . , wherein during deposition of the multilayer film at least one target comprising aluminum and chromium is operated as cathode by means of a PVD technique and used in this manner as material source for supplying aluminum and chromium, and an oxygen gas flow and a nitrogen gas flow are introduced as reactive gases in the vacuum chamber for reacting with aluminum and chromium, thereby supplying oxygen and nitrogen for forming the multilayer film, wherein:

• The A layers are deposited as oxynitride layers of Al—Cr—O—N by using nitrogen and oxygen as reactive gas at the same time,
• The B layers are deposited as nitride layers of Al—Cr—N by reducing the oxygen gas flow and by increasing the nitrogen gas flow in order to use only nitrogen as reactive gas for the formation of the Al—Cr—N layer, and
• wherein the relation between oxygen content and nitrogen content in the multilayer film correspond to a ratio in atomic percentage having a value between and including 1.8 and 4.

A steam turbine coated with a coating comprising a multilayer film, comprising aluminum, chromium, oxygen and nitrogen, deposited by using a method for producing a multilayer film in a vacuum coating chamber, the multilayer film comprising individual layers of type A and individual layers of type B deposited alternate one of each other forming a multilayered structure with sequence of individual layers B/A/B/A/B/A . . . , wherein during deposition of the multilayer film at least one target comprising aluminum and chromium is operated as cathode by means of a PVD technique and used in this manner as material source for supplying aluminum and chromium, and an oxygen gas flow and a nitrogen gas flow are introduced as reactive gases in the vacuum chamber for reacting with aluminum and chromium, thereby supplying oxygen and nitrogen for forming the multilayer film, wherein:

• The A layers are deposited as oxynitride layers of Al—Cr—O—N by using nitrogen and oxygen as reactive gas at the same time,
• The B layers are deposited as nitride layers of Al—Cr—N by reducing the oxygen gas flow and by increasing the nitrogen gas flow in order to use only nitrogen as reactive gas for the formation of the Al—Cr—N layer, and wherein the relation between oxygen content and nitrogen content in the multilayer film correspond to a ratio in atomic percentage having a value between and including 1.8 and 4.

A gas turbine coated with a coating comprising a multilayer film, comprising aluminum, chromium, oxygen and nitrogen, deposited by using a method for producing a multilayer film in a vacuum coating chamber, the multilayer film comprising individual layers of type A and individual layers of type B deposited alternate one of each other forming a multilayered structure with sequence of individual layers B/A/B/A/B/A . . . , wherein during deposition of the multilayer film at least one target comprising aluminum and chromium is operated as cathode by means of a PVD technique and used in this manner as material source for supplying aluminum and chromium, and an oxygen gas flow and a nitrogen gas flow are introduced as reactive gases in the vacuum chamber for reacting with aluminum and chromium, thereby supplying oxygen and nitrogen for forming the multilayer film, wherein:

• The A layers are deposited as oxynitride layers of Al—Cr—O—N by using nitrogen and oxygen as reactive gas at the same time,
• The B layers are deposited as nitride layers of Al—Cr—N by reducing the oxygen gas flow and by increasing the nitrogen gas flow in order to use only nitrogen as reactive gas for the formation of the Al—Cr—N layer, and
• wherein the relation between oxygen content and nitrogen content in the multilayer film correspond to a ratio in atomic percentage having a value between and including 1.8 and 4.

A component of a combustion engine coated with a coating comprising a multilayer film, comprising aluminum, chromium, oxygen and nitrogen, deposited by using a method for producing a multilayer film in a vacuum coating chamber, the multilayer film comprising individual layers of type A and individual layers of type B deposited alternate one of each other forming a multilayered structure with sequence of individual layers B/A/B/A/B/A . . . , wherein during deposition of the multilayer film at least one target comprising aluminum and chromium is operated as cathode by means of a PVD technique and used in this manner as material source for supplying aluminum and chromium, and an oxygen gas flow and a nitrogen gas flow are introduced as reactive gases in the vacuum chamber for reacting with aluminum and chromium, thereby supplying oxygen and nitrogen for forming the multilayer film, wherein:

• The A layers are deposited as oxynitride layers of Al—Cr—O—N by using nitrogen and oxygen as reactive gas at the same time,
• The B layers are deposited as nitride layers of Al—Cr—N by reducing the oxygen gas flow and by increasing the nitrogen gas flow in order to use only nitrogen as reactive gas for the formation of the Al—Cr—N layer, and
• wherein the relation between oxygen content and nitrogen content in the multilayer film correspond to a ratio in atomic percentage having a value between and including 1.8 and 4.