Master's candidate Yuwei Zhai and Professor Lados inspect an aluminum sample undergoing a test in a machine that can stretch metal until it breaks. Knowledge gained by testing alloys can lead to better computational tools and greater use of light metals in cars, trucks, and airplanes.
According to Lados, 90 percent of all mechanical
failures are caused by fatigue. Yet despite years of research, scientists still don't fully understand how those cracks form at the nano-level, especially in complex alloys. Nor have they managed to combine what they do know about small cracks with their understanding of large ones. That knowledge gap presents a problem, because without a clear picture of what's going on at every level, designers can't accurately predict how susceptible a particular metal will be to fatigue and failure under real operating conditions. So they build exces- sive weight into vehicle parts just to be safe. Using a combination of computational modeling and hands-on experimentation, Lados and her students plan to explore how small cracks form in the microstructures of metal parts, how they propagate and grow into larger fissures, and how all of this ultimately leads to failure. To gather data and validate their models, Lados and her team will prepare different light metal alloys, process them using novel techniques, then break them and examine the corpses.
The iMdc, whose mission is to advance the state of the
art and practice in sustainable materials, materials design, and manufacturing, will play a critical role in that process. Member companies, which represent all the transportation industries, along with manufacturing suppliers and metals producers, will use the alloys in real-world applications and help validate the tools and methods developed in the study. What Lados learns about the relationship between small cracks and big ones, how cracks form and spread, and how a material's properties influence fatigue will help metal manufacturers develop new and better alloys. It will also help designers more accurately predict the lifespan of their components. And that, in turn, should lead to increased use of lighter metals in everything from cars to boats to planes. That's all thanks to a little creative destruction — and
a generous application of the real-world wizardry at work in every corner of the Washburn Shops, magic that is transforming the field of modern metallurgy. Q
[15]