This EArly-concept Grant for Exploratory Research (EAGER) project will lay the scientific foundation for welding together?i.e., joining?of nanostructured materials. Traditional joining methods cannot be used because they destroy the desirable properties of these materials. Robust and scalable joining methods promise to accelerate the transition of nanostructured materials from the lab to engineering applications, thereby advancing the national interest. The approach to be explored relies on the self-organization of material structure into a strong and stable joint. This project will advance scientific understanding of the self-organization process. It will mentor one full-time postdoctoral researcher as well as provide research opportunities to undergraduates. Every effort will be made to recruit women and individuals from underrepresented minorities to the team. Furthermore, the PI will build up international research opportunities for students by developing a collaboration with a university in Mexico via the TAMU-CONACyT collaborative research grant program.
The goal of this project is to determine whether two adjacent nano-layered metal composites (NMCs) may be joined though the guided self-organization of an initially uniform filler material into a microstructure that interpolates the layered morphologies of two adjacent NMCs, connecting all the individual layers in them. Nano-layered metal composites (NMCs) possess numerous exceptional properties, such as high hardness, fatigue and radiation resistance, and excellent thermal stability. However, lack of joining methods that preserve the layered microstructure of NMCs impedes the technological use of these materials. Conventional joining methods?such as welding?disrupt the layered morphology of NMCs, thereby destroying their attractive properties. The novel joining process to be investigated here stands to create joints that preserve NMC properties by connecting the layers in them continuously, in effect interpolating their microstructures. The work combines experimental investigations with phase field modeling. Experiments will focus on small-scale testing of thin film materials synthesized using physical vapor deposition. The project will rely on lithographic techniques for creating well-defined gaps between NMCs and for plugging these gaps with customized filler materials. To guide the experimental effort, a phase field model will be developed to simulate both phase separation of the filler material as well as the subsequent evolution of the morphology of interpolating microstructures. This model will be used to pre-screen a range of processing conditions, focusing experimental effort on high-value regions of the processing parameter space.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
