About this Abstract |
Meeting |
MS&T21: Materials Science & Technology
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Symposium
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Additive Manufacturing of Metals: Microstructure, Properties and Alloy Development
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Presentation Title |
Microstructural and Strength Evolution during Aging of an Additively Manufactured Al-Cu-Mn-Zr Alloy |
Author(s) |
Richard A. Michi, Kevin Sisco, Sumit Bahl, Jonathan Poplawsky, Lawrence Allard, Ryan Dehoff, Alex Plotkowski, Amit Shyam |
On-Site Speaker (Planned) |
Richard A. Michi |
Abstract Scope |
Additive manufacturing enables the formation of unique microstructural features in high-temperature Al-Cu-Mn-Zr alloys. These features include a refined Al/θ-Al2Cu eutectic network, θ′-Al2Cu precipitates formed in situ during the build, and matrix supersaturations of solute elements. When heat treated, complex and simultaneous microstructural changes occur which dramatically affect strengthening mechanisms of the alloys, including coarsening of θ and θ′ precipitates and decomposition of the matrix solid solution by precipitation of nanometric L12-Al3Zr. In this talk, we review the microstructural changes occurring during aging at 300–400 °C and relate them to measured ambient- and high-temperature mechanical properties, including creep. An emphasis is placed on nanoscale microstructural and compositional analysis by APT and STEM. Insights gained are used to optimize heat treatments for alloy performance in the critical 250–400 °C temperature range. APT was conducted at the Center for Nanophase Materials Sciences (CNMS), a U.S. DOE Office of Science user facility. |