| About this Abstract |
| Meeting |
MS&T21: Materials Science & Technology
|
| Symposium
|
Development of Light Weight Alloys and Composites
|
| Presentation Title |
Coarsening of Strengthening Phases in Al(Cu) Alloys: Correlated Atomic-Resolution Microscopy and Composition Analysis |
| Author(s) |
Ujjval Bansal, Mahander Partap Singh, Shyam Kanta Sinha, Sukla Mondol, Kamanio Chattopadhyay |
| On-Site Speaker (Planned) |
Ujjval Bansal |
| Abstract Scope |
Strengthening by shear resistant θ"/θ' plates is the basis for developing high-temperature Al-Cu alloys. The addition of transition metals (TM) in Al(Cu) alloys form a coherent L12 ordered Al3TM phase that can further improve the microstructural stability and mechanical properties of these alloys. This talk will discuss the interaction between the evolved L12 and θ"/θ' precipitates leading to a coarsening resistant microstructure. STEM-EDS compositional studies show the enrichment of TM in the θ' plates. The presence of TM decreases the interfacial energy (thermodynamic factor) and act as a kinetic diffusion barrier to Cu atoms due to Zener drag (kinetic factor), eventually delaying the coarsening of θ' plates. Aberration-corrected STEM HAADF microscopy also detected anti-phase boundaries in L12 ordered precipitates which initiate phase transformation to a different phase on long-term ageing. |