Aluminizing of HVOF Sprayed CoNiCrAlY on IN738 by Ionic Liquid Electrolytic Deposition – Aluminizing Process and Coating Studies after Heat Treatment in Air
Aluminizing of HVOF Sprayed CoNiCrAlY on IN738 by Ionic Liquid Electrolytic Deposition – Aluminizing Process and Coating Studies after Heat Treatment in Air
Wednesday, May 9, 2018: 2:00 PM
Tampa 1 (Gaylord Palms Resort )
Aluminizing of HVOF Sprayed CoNiCrAlY on IN738 by Ionic Liquid Electrolytic Deposition – Aluminizing Process and Coating Studies after Heat Treatment in Air
M. Thoma1, L. Tagliaferri2, F. Bozza3,
1 MT Consulting, 2 Turbocoating Corp., 3 Turbocoating SpA
Inconel 738 (IN738) is a nickel-based superalloy widely used as a high temperature material for gas turbine applications. To protect the superalloy in service an environmental protective coating either an aluminide or a MCrAlY or a thermal barrier is necessary. The coating properties of Co-based MCrAlY coatings can be enhanced by over-aluminizing these MCrAlYs.
A novel aluminizing process based upon room temperature Al-electrodeposition from Ionic Liquids followed by diffusion heat treatment was applied on IN738 - bare and CoNiCrAlY coated by HVOF. The aluminized samples were tested at 1000 °C in air. The samples were analyzed in function of heat treatment time and compared with coatings obtained via pack cementation.
The diffusion of Al of the Ionic Liquid aluminizing process into the CoNiCrAlY coating and bare IN738 differs, but also in comparison to the pack cementation. The high diffusion of Ni of IN738 into the aluminized CoNiCrAlY coating after heat treatment is shown to convert the CoNiCrAlY coating to a NiCoCrAlY coating.
M. Thoma1, L. Tagliaferri2, F. Bozza3,
1 MT Consulting, 2 Turbocoating Corp., 3 Turbocoating SpA
Inconel 738 (IN738) is a nickel-based superalloy widely used as a high temperature material for gas turbine applications. To protect the superalloy in service an environmental protective coating either an aluminide or a MCrAlY or a thermal barrier is necessary. The coating properties of Co-based MCrAlY coatings can be enhanced by over-aluminizing these MCrAlYs.
A novel aluminizing process based upon room temperature Al-electrodeposition from Ionic Liquids followed by diffusion heat treatment was applied on IN738 - bare and CoNiCrAlY coated by HVOF. The aluminized samples were tested at 1000 °C in air. The samples were analyzed in function of heat treatment time and compared with coatings obtained via pack cementation.
The diffusion of Al of the Ionic Liquid aluminizing process into the CoNiCrAlY coating and bare IN738 differs, but also in comparison to the pack cementation. The high diffusion of Ni of IN738 into the aluminized CoNiCrAlY coating after heat treatment is shown to convert the CoNiCrAlY coating to a NiCoCrAlY coating.