Micro-cold Spray of Thick Films

We are currently studying the micro-cold spray process (AKA aersosol depostion method or vacuum kinetic spraying) for producing thick films of metals and ceramics.  Microcold spray utilizes nanometer to sub-micron powder particles as a feedstock. The particles are aerosolized and deaggomerated before accelerating them through a supersonic jet to velocities of 100-1200 m/sec and impacting them onto a substrate. By rastering the substrate beneath the jet nozzle, thick patterned lines can be directly written at high speeds and at room temperature. Compared to other processes, advantages of the microcold spray process include: 1) Nanostructured or amophous films from virtually any inorganic material can be produced 2) Highly non-equilibrium nanostructured composites can be deposited which exhibit unique and potentially advantageous properties 3) Films with thicknesses of more than 100 µm can be produced 4) Films can be patterned at high velocity and without the need for device-specific tooling 5) Since films are deposited at room temperature, polymeric substrates can be used and 6) the impaction velocities can be controlled, allowing films with a large range of densities to be produced.  We use a combination of experiments and molecular dynamics simulations to study the relationships between processing parameters and microstructur. The aim is to use these processes to direct-write high quality, micro-scale devices or films made from polymers, metals and ceramics.

Collaborators

• Michael Gammage, Army Research Laboratory

•Michael Becker, University of Texas at Austin

•John Keto, University of Texas at Austin


Current Post-Doctoral Researchers and Graduate Student Researchers

•Emmanuel Ekoi

•Stephen Bierschenk

•Scott Burlison

•Richard Clore

•Liam McAuliffe


This work is currently supported by the US Army Research Laboratory, the National Science Foundation, DARPA, Sandia National Laboratories, and Los Alamos National Laboratory.

Publications