2019 Dennis & Leslie Drag Distinguished Lecture
Ductility: Another View
A Presentation by Duane K. Miller, Sc.D., P.E.
Manager, Engineering Services, Welding Design Consultant
The Lincoln Electric Company, Cleveland, Ohio
Wednesday, Oct. 9, 2019, 4:30pm - ME 1061
Reception in Wood Commons (Hampton Hall) at 3:30pm
It is often said that "steel is an inherently ductile material" and yet this statement fails to explain how steel occasionally behaves in a brittle manner. Most texts include in the listing of mechanical properties both yield and tensile strengths, as well as other, and yet sometimes, steel fails with no sign of yielding before fracture. Structural engineers designing structures to resist earthquake loading rely on ductile behavior to absorb seismically-induced loads, and yet brittle fractures have been observed after earthquakes. These apparent paradoxes can be understood when the role of shear stresses and ductility is properly understood. Notches and constraint, known to be problematic when ductility is desired, can also be explained in terms of shear stresses. Designing structural systems to enable the development of shear stresses is essential if ductility is desired. This presentation will give insight into how ductility can be achieved and provide some insight into how Mohr's Circle can be used to easily explain ductility.
Duane K. Miller, Sc.D., P.E., is a recognized authority on the design and performance of welded connections and has lectured around the world. Dr. Miller publishes frequently and on three occasions, has been awarded the Silver Quill Award of the American Welding Society (AWS) for the excellence of his published work. In 2015, he was named an AWS Fellow. He received the American Institute of Steel Construction's T. R. Higgins Lectureship Award in 2001, the AISC Lifetime Achievement Award in 2005, and became the eighth recipient of the AISC Robert P. Stupp Award for Leadership Excellence in 2016; he became the first recipient of the AISC Steel Conference Speaker Award in 2018. He was appointed an Adjunct Professor at the University of Alberta in 2019. He is a Professional Engineer, and formerly a Certified Welding Inspector and Qualified Welder.