| About this Abstract |
| Meeting |
MS&T23: Materials Science & Technology
|
| Symposium
|
Metal Powder Synthesis and Processing: Fundamental Aspects and Modeling
|
| Presentation Title |
Effect of Li Concentration on Morphology of Precipitates in Nanocrystalline Cu-3Ta |
| Author(s) |
Joshua Smeltzer, B. Chad Hornbuckle, Kiran Solanki, Martin Harmer, Kristopher Darling, Christopher J. Marvel |
| On-Site Speaker (Planned) |
Christopher J. Marvel |
| Abstract Scope |
Formation and stability of coherent interfaces between precipitates and an alloy matrix has been an effective strategy for enhancing material strength, particularly in advanced Al- and Ni-based alloys. Nanocrystalline Cu-3Ta has proceeded down a similar evolutionary path with the development of coherent/semi-coherent Ta-based clusters/precipitates that both stabilize the nanoscale microstructure and improve strength, hardness, and irradiation resistance, amongst other properties. This talk will present further progress towards refining coherent interfaces in Cu-3Ta. Here, Cu-3Ta alloys with different Li concentrations were synthesized, annealed up to 97% Tm, and characterized by applying aberration-corrected scanning transmission electron microscopy to assess coherency relationships. The key observations were that Li additions prompted a morphological evolution from spherical Ta-based clusters to cuboidal Li-enriched precipitates, and that Ta-based complexions were observed on all precipitates, thus suggesting that Ta-rich complexions relax interfacial misfit strains that would otherwise drive a shift from coherent to unfavorable incoherent phase boundaries. |