Until I was eight years old I lived in Salzburg, Austria. My family then relocated to a small town called Grande Prairie in Alberta, Canada, where I lived until I left for college. I received my B.Sc. degree in mechanical engineering from the University of Calgary. Concurrent to my studies in mechanical engineering I completed a specialization in biomedical engineering, which links two disciplines that have always interested me: engineering and medicine. My first introduction to engineering research was at the Calgary Center for Innovative Technology, where I worked during the summer after my sophomore year. Exactly one year later I found myself working here at Northwestern University. It was then that I was first exposed to materials science, which immediately appealed to me because it approaches engineering problems at a very fundamental level.
The research of my Ph.D. focuses on a very unique material called nickel titanium (NiTi). This metal belongs to a special class of alloys exhibiting the shape memory effect; it can undergo very high deformations and yet return to its original shape after heating it above a particular temperature. How is this possible? The trick is that, while regular materials deform irreparably via diffusion mechanisms, nickel titanium deforms by simply changing the orientation of its crystallographic planes. This process is diffusionless and therefore reversible. Heating the material and cooling it down again essentially returns the planes to their original orientation. In fact, by tailoring the material composition it is possible to produce a super-elastic alloy, which no longer requires heat to return from exceptionally high deformations to its original shape.
These and other properties make NiTi a very promising candidate for orthopedic implants. For this application it would be highly desirable to introduce pores into the material so as to structurally mimic the surrounding bone. NiTi foams also have potential as shock absorbers and actuators. Porous NiTi has been previously created in the Dunand group through the application of powder metallurgy techniques. I will be trying new foaming methods that have been successfully used on titanium in order to increase control over pore shape and distribution.
