Description:

Nanotribology, Nanomechanics and Materials Characterization Studies and Applications to Bio/Nanotechnology and Biomimetics

Abstract
At most solid-solid interfaces of technological relevance, contact occurs at numerous asperities. A sharp atomic/friction force microscope (AFM/FFM) tip sliding on a surface simulates just one such contact. However, asperities come in all shapes and sizes that can be simulated using tips of different shapes and sizes. AFM/FFM techniques are commonly used for tribological studies of engineering surfaces at scales ranging from atomic- to microscales. Studies include surface characterization, adhesion, friction, scratching/wear, boundary lubrication, electrical resistance, surface potential, and capacitance mapping. AFMs and their modifications are also used for nanomechanical characterization, which includes measurement and analysis of hardness, elastic modulus and viscoelastic properties, and in-situ localized deformation studies. The experimental data exhibit scale effects in adhesion, friction, wear, and mechanical properties. Generally, coefficients of friction and wear rates on micro- and nanoscales are smaller, whereas hardness is greater. Therefore, micro/nanotribological studies may help define the regimes for ultra-low friction and near-zero wear. New lubrication strategies such as the use of self-assembled monolayers promise to be very versatile and effective at these scales.
Nanotribology and Nanomechanics of various MEMS/NEMS and BioMEMS/BioNEMS devices which require relative motion is of importance4. The scale of operation and large surface-to-volume ratio of the devices result in very high retarding forces such as friction and adhesion that seriously undermine the performance and reliability of the devices. Carbon nanotubes are being used for various nanotechnology applications. The mechanical strength and reliability of many of these devices critically relies on the nanotribology and nanomechanics of the CNTs5. There are bioadhesion issues in biosensors and other BioMEMS/BioNEMS which need to be addressed.
Biologically inspired design, adaptation, or derivation from nature is referred to as biomimetics. The understanding of the functions provided by objects and processes found in nature can guide us to imitate and produce nanomaterials, nanodevices, and processes.
These fundamental nanotribological studies provide insight to the molecular origins of interfacial phenomena including adhesion, friction, wear, and lubrication. Friction and wear of lightly loaded micro/nano components are highly dependent on surface interactions within a few atomic layers. Nanotribological and nanomechanics studies are also valuable in the fundamental understanding of interfacial phenomena in macrostructures to provide a bridge between science and engineering. This talk will present an overview of nanotribological and nanomechanics studies and their applications to bio/nanotechnology and biomimetics.

Bio
Dr. Bharat Bhushan is an Ohio Eminent Scholar and The Howard D. Winbigler Professor in the College of Engineering, and the Director of the Nanoprobe Laboratory for Bio- & Nanotechnology and Biomimetics (NLB2) and affiliated faculty in John Glenn College of Public Affairs at the Ohio State University, Columbus, Ohio. In 2013-14, he served as an ASME/AAAS Science & Technology Policy Fellow, House Committee on Science, Space & Technology, United States Congress, Washington, DC. He holds two M.S., a Ph.D. in mechanical engineering/mechanics, an MBA, and two honorary and two semi-honorary doctorates. His research interests include fundamental studies with a focus on scanning probe techniques in the interdisciplinary areas of bio/nanotribology, bio/nanomechanics and bio/nanomaterials characterization and applications to bio/nanotechnology, and biomimetics. He has authored 8 scientific books, 90+ handbook chapters, 800+ scientific papers (One of Google Scholar’s 1745 Highly Cited Researchers (h>100), h-index - 120+ with 70k+ citations, i10-index - 725+; Web of Science h-index - 90+; Scopus h-index - 95+; ISI Highly Cited Researcher in Materials Science since 2007 and in Biology and Biochemistry, 2013; ISI Top 5% Cited Authors for Journals in Chemistry, 2011; Clarivate Analytics Highly Cited Researcher in Cross-field Category, 2018), and 60+ technical reports. He has also edited 50+ books and holds more than 25 U.S. and foreign patents. He is co-editor of Springer NanoScience and Technology Series and Microsystem Technologies, and member of editorial board of PNAS. He has given more than 400 invited presentations on six continents and more than 200 keynote/plenary addresses at major international conferences. He has delivered a TEDx 2019 lecture.

He has organized various international conferences and workshops. He is the recipient of numerous prestigious awards and international fellowships including the Alexander von Humboldt Research Prize for Senior Scientists, Max Planck Foundation Research Award for Outstanding Foreign Scientists, Fulbright Senior Scholar Award, Life Achievement Tribology Award, and Institution of Chemical Engineers (UK) Global Award. His research was listed as the top ten science stories of 2015. He is a member of various professional societies, including the International Academy of Engineering (Russia). He has previously worked for various research labs including IBM Almaden Research Center, San Jose, CA. He has held visiting professorship at University of California at Berkeley, University of Cambridge, UK, Technical University Vienna, Austria, University of Paris, Orsay, ETH Zurich, EPFL Lausanne, Univ. of Southampton, UK, Univ. of Kragujevac, Serbia, Tsinghua Univ., China, Harbin Inst., China, and KFUPM, Saudi Arabia.