• Dahlqvist, Martin
• Löfler, Lukas
• Holzapfel, Damian
• Schneider, Jochen M.
• Rosen, Johanna
• Mendez, Alba San Jose
• Azina, Clio
• Hans, Marcus
• Primetzhofer, Daniel
• Bartsch, Tim

Abstract

<jats:title>Abstract</jats:title><jats:p>Herein we report on the synthesis of a metastable (Cr,Y)<jats:sub>2</jats:sub>AlC MAX phase solid solution by co‐sputtering from a composite Cr–Al–C and elemental Y target, at room temperature, followed by annealing. However, direct high‐temperature synthesis resulted in multiphase films, as evidenced by X‐ray diffraction analyses, room‐temperature depositions, followed by annealing to 760°C led to the formation of phase pure (Cr,Y)<jats:sub>2</jats:sub>AlC by diffusion. Higher annealing temperatures caused a decomposition of the metastable phase into Cr<jats:sub>2</jats:sub>AlC, Y<jats:sub>5</jats:sub>Al<jats:sub>3</jats:sub>, and Cr‐carbides. In contrast to pure Cr<jats:sub>2</jats:sub>AlC, the Y‐containing phase crystallizes directly in the MAX phase structure instead of first forming a disordered solid solution. Furthermore, the crystallization temperature was shown to be Y‐content dependent and was increased by ∼200°C for 5 at.% Y compared to Cr<jats:sub>2</jats:sub>AlC. Calculations predicting the metastable phase formation of (Cr,Y)<jats:sub>2</jats:sub>AlC and its decomposition are in excellent agreement with the experimental findings.</jats:p>

Topics

• Deposition
• thin film
• carbide
• composite
• forming
• Yttrium
• annealing
• crystallization
• decomposition
• crystallization temperature
• metastable phase