This title appears in the Scientific Report : 2013 

Interaction of vacuum plasma-sprayed protective bond coats with γ/γ`-strengthened Co-base superalloys during thermal treatment
Terberger, Philipp (Corresponding author)
Sebold, Doris / Vaßen, Robert
Werkstoffsynthese und Herstellungsverfahren; IEK-1
Gordon Research Conf. "High Temperature Corrosion", New London (USA, NH), 2013-07-21 - 2013-07-26
Helmholtz Interdisciplinary Doctoral Training in Energy and Climate Research (HITEC)
Power Plants
In this poster the interaction of vacuum plasma-sprayed (VPS) protective bond coats and γ/γ`-strengthened Co-base superalloys during thermal treatment is presented. γ/γ`-strengthened Co-base superalloys are currently investigated with the aim of utilizing them for high-temperature, high-load applications in gas turbine blades, as these alloys show improved corrosion resistance and higher operating temperatures compared to Ni-base superalloys. Those blades are often protected by a thermal barrier coating system (TBC) consisting of a metallic bond coat for corrosion and oxidation resistance and a ceramic top coat. Plasma-sprayed MCrAlY bond coats (M=Co,Ni) are commonly used for this application. For the new Co-base superalloys the interaction with the adjacent bond coat needs to be studied to ensure their compatibility. To do this, MCrAlY-coated Co-base superalloy samples were thermally treated at 900 °C and analysed using SEM and EDX. In this work current results are presented with an emphasis on the interdiffusion behaviour. Phases formed in the interdiffusion zone are identified and analysed. It was found, that interdiffusion leads to dissolving of the γ`-phase in the superalloy and formation of various W-rich phases.