|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Materials for High Temperature Applications: Next Generation Superalloys and Beyond
||The Influence of Ta and Ti on Heat-treatability and γ/γ’-partitioning of High W Containing Re-free Nickel-based-superalloys
||Nils Christian Ritter, Ralf Rettig, Robert Singer
|On-Site Speaker (Planned)
||Nils Christian Ritter
This investigation deals with alloys designed by systematically varied amount of Ta and Ti to analyze their effect on heat treatability and partitioning behavior of the solid solution strengthening element W. Ta is more effective in shifting W partitioning behavior towards matrix phase compared to Ti whereas the combination of both reaches even better results. This behavior improves solid-solution-strengthening of the matrix phase. Ta stabilizes γ’-phase at high temperature more effectively compared to Ti but also increases the dissolution temperature of eutectic fraction. The combination of Ta and Ti is increasing eutectic fraction hardly whereas segregation is most severe in alloys containing only Ti. The solidus- and liquidus-temperature is strongly reduced by Ta+Ti and only Ti containing alloys. Therefore Ta is the better γ’ forming and strengthening element for maximum creep-performance at highest application-temperatures whereas Ti is useful in applications with great significance of density at intermediate temperatures.