Lei Research Group

Project 1. Cold-spray metallization of carbon fiber reinforced polymer composites (funded by AFOSR)

In this project, our goal is to join and repair carbon fiber reinforced polymer composites using cold spray to deposit functionally graded metallic layers. We aim to achieve an optimal combination of mechanical properties, corrosion resistance, and electrical conductivity.

The video (right) shows one representative cold spray experiment conducted at the CAMMDI center at the University of Alabama.

This project is supported by the Air Force Office of Scientific Research.

Project 2. Developing high-performance aluminum alloys by engineering grain boundaries and associated grain boundary precipitates

In this project, we aim to enhance the performance of aluminum alloys for aerospace applications by elucidating the effects of grain boundary segregation and related microstructural features, including grain boundary precipitates, on mechanical properties and thermal stability of both conventional and newly developed alloy systems.

The figure (right) shows how we utilize nanoscale grain boundary precipitates, grain boundary segregation, and grain boundary structural transitions to achieve centimeter-sized aluminum samples with nanosized grains.

Bulk aluminum alloy sample fabricated via grain boundary engineering

Project 3. Additive manufacturing bulk metallic glasses components by tailoring nanoscale inhomogeneity

In this project, our goal is to enhance the cold sprayability of metallic glasses for the fabrication of bulk components. We will leverage the nanoscale heterogeneity within metallic glasses to tune the deformation behavior upon impact, thereby enhancing the deposition efficiency and densification of metallic glass components processed by cold spray deposition.

The image (right) shows an atom probe tomography reconstruction revealing the presence of nanosized atomic clusters within a metallic glass.