Michael Aderibigbe ’28 PhD studies metals at the microscopic scale. His work is part of the larger field of materials science, which involves uncovering the unique properties of metals. Materials science has given rise to many of the latest advancements in computing, medicine, and telecommunications; its discoveries are integral to our daily lives.
After studying mechanical engineering and taking some classes in materials science at Lagos State University, Aderibigbe knew he wanted to continue in that field. He was especially interested in the work of Jan Schroers, the Robert Higgin Professor of Materials Science and Mechanical Engineering at Yale Engineering. “Jan’s research, and Yale’s reputation, really reeled me in,” he says. “I knew this was where I wanted to go for my PhD.”
Aderibigbe’s intuition paid off. “Jan is quite easy to talk to, and very helpful in clarifying things,” he says.
In the lab, Aderibigbe’s work involves studying the underlying, microscopic structures—or microstructures—of different metals in order to better understand and identify their properties. His work combines experiments, theoretical modeling, and advanced materials processing.
He has also helped to develop a new technique for measuring how atoms move through metal, called diffusion. Establishing the diffusivity of different metals, he says, helps engineers understand how different metals are likely to behave under various conditions. The traditional method uses radioactive isotopes, or radioisotopes, of the metal in question. This can take several days as the radioisotopes diffuse into the metal. Some metals also have radioisotopes with very short half-lives which decay before they can penetrate into the test metal, making them impossible to study using the traditional method.
Aderibigbe is working on a different method that involves identifying how different features of the metal’s microstructures contribute to the metal’s overall properties without the need for radioisotopes. The new method takes only a few hours. He heats the metal and then squeezes it through almost impossibly small cavities, smaller than the diameter of a human hair, creating fine strands called nanowires. It’s a bit like pressing Play-Doh through an extruder. The resulting nanowires give Aderibigbe information about how each aspect of the metal’s underlying structure affects its diffusivity.
These nanowires are also very useful in the semiconductor industry, where things get faster and more accurate the smaller they are, Aderibigbe says. Nanowires, at their small scales and with high surface-area-to-volume ratios, have unique electrical, optical, and thermal properties that are difficult to achieve with larger, more conventional structures.
When he’s not contorting metals, Aderibigbe likes to play soccer, joining friends every Sunday on the fields near the Yale Bowl.
Although Aderibigbe’s work has broad commercial applicability for improving microchips, nanoscale sensors, and other crucial electronics components, he wants to remain in academia after finishing his PhD. And where would his first choice be to teach? “Yale, of course,” he says. “It’s a great place.”