Reginald Hamilton, Ph.D.
Associate Professor of Engineering Science and Mechanics
Penn State University
The goal of this project is to design lamellar (multilayered) shape memory alloy structures (LSMAS) for additive manufacturing (AM) and demonstrate the ability to engineer the AM build plan to tune the performance. We employ laser directed energy deposition additive manufacturing (LDED) using elemental Ni and Ti powder. Our approach will correlate bulk/meso-scale shape memory properties to the hierarchical microstructure using high throughput local measurements.
AM of LSMAS will enable on-demand, customizable multifunctionality. The localized nature of AM (i.e. layer-/pass-wise build-up) produces interfaces between the build layers and between lamellae resulting in novel microstructures in stark contrast to the conventional fabrication of wrought sheet, rod, wire, etc. To tune the performance, we correlate the hierarchical microstructure resulting from AM, to the multi-scale SMA deformation mechanism – an atomic structure change begets a reversible martensitic microstructure solid-state phase transformation that facilitates shape recovery.
Materials Science & Engineering Dept.