Materials Science Research Lecture

Webinar Link:

https://caltech.zoom.us/j/83276652110

Webinar ID: 832 7665 2110

***Note, this week's MRL held on Friday due to TMS Conference

NOTE: At this time, in-person APhMS seminars are open to all Caltech students/staff/faculty/visitors with a valid Caltech ID. Outside community members are welcome to join our online event.

Abstract:

Since its introduction and development more than three decades ago, nanoindentation has gained widespread acceptance as a tool for measuring and mapping the mechanical properties of thin films, thin surface regions, and small volumes of material. Hardness and elastic modulus are the most routinely measured properties, but techniques have also been developed for estimating fracture toughness, yield stress, strain hardening, creep, strain rate sensitivity, and residual stress. Much of the utility of the technique accrues from its ability to measure many of these properties from indentation contacts only a few nanometers deep. This presentation will focus on recent developments of two new and emerging nanoindentation measurement tools: (1) a new testing system and methods for performing fully instrumented nanoindentation at very high strain rates (up to 105/s), and (2) a multiaxial nanoindentation testing that may be particularly useful for studying friction at the micron- and sub-micron scales.

More about the Speaker:

George M. Pharr is Professor of Materials Science and Engineering and Erle Nye '59 Chair I at Texas A&M University, College Station TX. He received his BS in Mechanical Engineering at Rice University in 1975 and Ph.D. in Materials Science and Engineering from Stanford in 1979. After one year of postdoctoral study at the University of Cambridge, he returned to Rice in 1980 as a faculty member in the Department of Mechanical Engineering and Materials Science. He moved to the Department of Materials Science and Engineering at the University of Tennessee (UT) in 1998, and to Texas A&M in 2017. While at UT, he served a term as Head of the Materials Science and Engineering Department and held a Joint Faculty Appointment at the Oak Ridge National Laboratory (ORNL). Pharr is a member of the National Academy of Engineering and a Fellow of three professional societies: TMS, ASM International, and the Materials Research Society. He serves as an Associate Editor of the Journal of the American Ceramic Society and Principal Editor for the Journal of Materials Research. His research focuses on mechanisms of plasticity and fracture in solids, especially at small scales.