|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Phase Transformations and Microstructural Evolution
||Precipitation Behavior of Strengthening Phases in a High Temperature Aluminum-cerium Alloy
||Opemipo Adetan, Dinc Erdeniz
|On-Site Speaker (Planned)
The use of cerium as a major alloying element for aluminum is gaining more attention in recent years due to the castability of this binary alloy system and the high-temperature stability of the Al11Ce3 intermetallic phase, which forms upon eutectic solidification and provides strengthening. Despite the apparent advantageous properties of these alloys, they still suffer from high creep rates at elevated temperatures, due to a lack of strengthening within the aluminum solid-solution channels. Micro-alloying with scandium and zirconium enables additional strengthening via the formation of L12– ordered, tri-aluminide precipitates, which improves the creep resistance. In this work, castable Al-Ce-Sc-Zr alloys are designed using the CALPHAD methodology and subjected to various heat treatments. The precipitation and thermal stability of these two strengthening phases, Al11Ce3 and Al3(Sc,Zr), are investigated using micro/nano characterization techniques. Compression creep tests are carried out to evaluate the effect of the tri-aluminide precipitates on high temperature strength.
||Aluminum, High-Temperature Materials, Phase Transformations