CSIR Central

High Temperature Oxidation Resistant Modified NiCoCrAlY Coating

IR@NAL: CSIR-National Aerospace Laboratories, Bangalore


Field	Value

Title	High Temperature Oxidation Resistant Modified NiCoCrAlY Coating

Creator	Srivastava, Meenu Balaraju, JN Ravisankar, B

Subject	Metals and Metallic Materials

Description	High temperature components such as moving and stationary blades of jet engines and gas turbines, combustors, boiler tubes are often surface coated for improving their oxidation and hot corrosion resistance. An oxide film protecting the substrate is formed by an overlay coating layer of type MCrAlY. The MCrAlY coating can be obtained by various methods like plasma spraying, electron–beam physical vapour deposition, high velocity oxy fuel etc. Despite the flexibility of these processes their infrastructure and the operating costs are high. Electrodeposition is another method which can be used to develop this coating. These coatings upon exposure to high temperatures (800o to 1200oC), the Al and Cr atoms tend to diffuse inward into the substrate from the coating layer and the substrate elements diffuse outward into the coating, as a result the protective oxide loses its protective ability with time. The mutual diffusion between the coating and substrate causes deterioration of mechanical properties of the substrate. Hence, there is a need for a barrier layer to prevent diffusion between the coating and substrate. The present work provides a method to obtain high temperature oxidation resistant coatings by a combination of electroless deposited diffusion barrier layer and electrodeposited metallic MCrAlY coating.

Date	2013-12-05

Type	Conference or Workshop Item PeerReviewed

Format	application/pdf

Identifier	http://nal-ir.nal.res.in/12294/1/cp75.pdf Srivastava, Meenu and Balaraju, JN and Ravisankar, B (2013) High Temperature Oxidation Resistant Modified NiCoCrAlY Coating. In: ASME 2013 Gas Turbine India Conference, 5-6 Dec 2013, NAL, Bengaluru.

Relation	http://nal-ir.nal.res.in/12294/