When Yashashree Kulkarni isn’t singing opera (her latest pursuit), the associate professor of mechanical engineering is singing the praises of twinning, the process by which interfaces known as twin boundaries are introduced in metals to make them stronger. Twin boundaries are created when layers of atoms in crystalline materials are arranged in pairs of mirror images (twins) stacked on top of one another.
“For all structural applications, we want a material that is both ultra-strong and not brittle – we call it ductile – and that is what we do with twinning,” said Kulkarni.
Here’s what she also does: Picks up awards for her work on nanotwinned metals, most recently from the American Society of Mechanical Engineers (ASME). The organization chose her as winner of the 2017 Sia Nemat-Nassar Early Career Award for her “pioneering work on twin boundaries in crystalline materials and their role in next-generation nanostructured materials,” according to ASME.
“It’s a very prestigious award. It is national-level recognition and I am really humbled by it,” said Kulkarni.
Kulkarni received her Ph.D. in 2007 and has a career reel of highlights in the field of computational modeling of twins in nanostructured materials.
She has explored the ability of specially fabricated nanotwinned metals to withstand prolonged exposure to high radiation through a grant from the National Science Foundation; and, she is an early pioneer of studying twin boundaries at the molecular level to understand their role in imparting high strength, ductility, and mechanical stability to nanotwinned metals.
But the overarching focus of her work, she says, is to understand how twin boundaries interact with other defects, because, as she notes, there are always going to be defects in materials, and they ultimately determine the mechanical behavior of the material.
“Whenever a material deforms or ultimately fails, it all starts at the scale of atoms, where defects are formed breaking the crystalline order,” said Kulkarni. “My work has been mostly on how these unique twin boundaries interact with the defects that are already present or formed during deformation to make the material stronger.”
She recalls a quote by Sir Colin Humphreys, a famous materials scientist, that she works and lives by: “Crystals are like people; It is the defects in them that tend to make them interesting.”
Sounds almost operatic.