The development of refractory complex concentrated alloys (RCCAs) attracts a lot of attention to replace Nickel based superalloys as structural high-temperature materials. Recently, a superalloy like microstructure was found in several systems, including alloys based on the AlMoNbTaTiZr system. However, instead of forming fcc/L12 phases, the microstructure consists of bcc/B2. While having promising mechanical properties at temperatures around 1000 °C, some alloy compositions even show room temperature ductility in compression. However, the effect of each alloying element on the microstructure and the mechanical properties is still not clear, yet.
This talk aims to shed some light on the effect of different alloying elements and heat treatment conditions on the microstructure and mechanical properties in the AlMoTaTi system. Therefore, alloys with varying composition were produced by repetitive arc-melting and heat treated at temperatures up to 1600 °C. For microstructural characterization, SEM/TEM were used. Hardness testing and compression testing determined mechanical properties.