Coated part comprising a protective coating based on MAX phases

A method for manufacturing a coated part comprising a metallic substrate,

• a thermal barrier comprising a ceramic material and covering the metallic substrate, wherein the coated part further comprises a protective coating covering the thermal barrier, the protective coating comprising, in a first region, a first MAX phase, denoted PZ2, of formula (ZrxTi1-x)2AlC or a first MAX phase, denoted PC2, of formula (CrxTi1-x)2AlC with x non-zero and less than or equal to 1 in the MAX phases PZ2 and PC2, and the protective coating comprising, in a second region covering the first region, a second MAX phase of formula Ti2AlC and with x less than 1 in the MAX phases PZ2 and PC2,
• the method comprising, when the first region comprises the first MAX phase PZ2:
• depositing zirconium or a zirconium alloy on the thermal barrier, the deposit being made by a spray technique, by a vapour phase deposition technique, by sol-gel route or electrophoresis,
• depositing the second MAX phase of formula Ti2AlC on the previously deposited zirconium or zirconium alloy, the deposit being made by a spray technique, by a vapour phase deposition technique, by sol-gel route or electrophoresis, and
• a heat treatment for zirconium diffusion into the second MAX phase of formula Ti2AlC by imposing a temperature greater than or equal to 900° C. in order to obtain the coated part,
• or the method comprising, when the first region comprises the first MAX phase PC2:
• depositing chromium or a chromium alloy on the thermal barrier, the deposit being made by a spray technique, by a vapour phase deposition technique, by sol-gel route or electrophoresis, depositing the second MAX phase of formula Ti2AlC on the previously deposited chromium or chromium alloy, the deposit being made by a spray technique, by a vapour phase deposition technique, by sol-gel route or electrophoresis, and
• a heat treatment for chromium diffusion into the second MAX phase of formula Ti2AlC by imposing a temperature greater than or equal to 900° C. in order to obtain the coated part.

A method for manufacturing a coated part, comprising a metallic substrate,

• a thermal barrier comprising a ceramic material and covering the metallic substrate,
• wherein the coated part further comprises a protective coating covering the thermal barrier, the protective coating comprising, in a first region, a first MAX phase, denoted PZ3, of formula (ZrxTi1-x)3AlC2 or a first MAX phase, denoted PC3, of formula (CrxTi1-x)3AlC2 with x non-zero and less than or equal to 1 in the MAX phases PZ3 and PC3, and the protective coating comprising, in a second region covering the first region, a second MAX phase of formula Ti3AlC2,
• the method comprising, when the first region comprises the first MAX phase PZ3:
• depositing zirconium or a zirconium alloy on the thermal barrier, the deposit being made by a spray technique, by a vapour phase deposition technique, by sol-gel route or electrophoresis,
• depositing the second MAX phase of formula Ti3AlC2 on the previously deposited zirconium or zirconium alloy, the deposit being made by a spray technique, by a vapour phase deposition technique, by sol-gel route or electrophoresis, and
• a heat treatment for zirconium diffusion into the second MAX phase of formula Ti3AlC2 by imposing a temperature greater than or equal to 900° C. in order to obtain the coated part, or the method comprising, when the first region comprises the first MAX phase PC3:
• depositing chromium or a chromium alloy on the thermal barrier, the deposit being made by a spray technique, by a vapour phase deposition technique, by sol-gel route or electrophoresis,
• depositing the second MAX phase of formula Ti3AlC2 on the previously deposited chromium or chromium alloy, the deposit being made by a spray technique, by a vapour phase deposition technique, by sol-gel route or electrophoresis, and
• a heat treatment for chromium diffusion into the second MAX phase of formula Ti3AlC2 by imposing a temperature greater than or equal to 900° C. in order to obtain the coated part.