Micro and nanomechanics at high strain rates (28/04/22)
Speaker and Affliation:
Dr. Rajaprakash Ramachandramoorthy
Max-Planck-Institut für Eisenforschung (Germany)
Biography
Dr. Rajaprakash Ramachandramoorthy was born in Virudhunagar, Tamil Nadu India. He received his Bachelor’s degree in Aerospace Engineering from both University of Glasgow (Scotland, UK) and University of Illinois Urbana Champaign (USA). He then moved to McGill University (Montreal, Canada) to earn his Master’s degree in mechanical engineering, where he worked on laser transmission welding of thermoplastic composites using laser refraction. He then earned his PhD in Theoretical and Applied Mechanics at Northwestern University (USA) on the topic: Deformation and failure in metallic nanowires under stress-relaxation, cyclic and high strain rate loading conditions. Further, he joined Empa – Swiss federal laboratories for materials science and technology, Switzerland as a Marie-Curie postdoctoral fellow to research on high strain rate testing of microscale materials at extreme temperatures and templated electrodeposition based micromanufacturing. In August 2020, he joinedMax-Planck-Institut für Eisenforschung (Germany) as Group Leader of Nanomechanical instrumentation and extreme nanomechanics (XNano) group, which focuses on developing testing platforms and the necessary protocols/methods to conduct nano-to-meso scale mechanical testing under extreme strain rates/ temperatures and localized electrodeposition-based 3D printing of metallic micro/nano architectures.
When?
28th April, 2022 (Thursday), 11:00 AM (India Standard Time)
Where
Department of Materials Engineering, KPA auditorium
Abstract
Dynamic properties of materials are vital to assess their suitability and reliability in applications ranging from common drops to demanding impact-protection applications. The field of macroscale dynamic testing was established in the 1940’s specifically for assessing the mechanical behavior of materials under extreme strain rates. But given the push towards miniaturization, micro and nano scale parts have recently become ubiquitous and functional parts in a variety of applications. As such, small scale mechanics has been a topic of intense research over the last two decades. However, to date the micro and nanomechanical experiments have been limited to quasi-static testing speeds and the behavior of small-scale materials under extreme strain rates remains largely unexplored experimentally. In this presentation, I will introduce testing platforms required to conduct micro and nano-scale mechanical metrology at high strain rates. Specifically, I will present a microelectromechanical systems (MEMS) based nanomechanical testing platform capable of performing high strain rate testing, along with a case study on single crystalline silver nanowires. In the second part of my talk, I will introduce a localized electrodeposition-based additive micromanufacturing (AMM) technique capable of fabricating full-metal 3D micro/nano architectures. Subsequently, case studies on the dynamic mechanical characterization of copper micropillars and microlattices built using AMM, along with complementary microstructural characterization will be presented.