Topic: Additive manufacturing of metals: tailoring microstructures for high mechanical performance and reliability

Speaker: Prof. Upadrasta Ramamurty 

School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798 

Time: 14:00-15:30 (Thu.), May. 23^rd, 2019 

Venue: Room 403, Shi Changxu Building, IMR CAS  

Abstract:  

Additive manufacturing of metallic components using the selective laser melting (SLM) of powders offers a number of technological advantages and hence, is of considerable current interest for advanced engineering applications. From the scientific perspective, this process offers a number of exciting opportunities, some of which I will discuss in this talk. The SLM process imparts not only a fine microstructure but also distinct mesostructure that depends on the process parameter combinations employed. A complex interplay between these micro- and meso-structural features can lead to property combinations that were hitherto thought as not possible. In this presentation, some examples as to how all these features will affect the mechanical properties through a comprehensive microstructural and mechanical property characterization of several different alloy components made through SLM will be presented, with particular emphasis on understanding their quasi-static tensile, fracture, fatigue crack growth, and unnotched fatigue properties. Possible avenues for further improvements in properties through post-SLM heat treatments will be discussed. 

Biography:  

Prof. U. Ramamurty did his PhD Brown University under the guidance of S. Suresh. After Post-doctoral stints at UCSB and MIT, he held faculty positions at NTU, Singapore, and IISc, Bangalore, before returning to NTU in August 2018 where he is currently the President's Chair Professor of Mechanical & Aerospace Engineering and Materials Science & Engineering. His current research interests include deformation and fracture behavior of amorphous as well as crystalline alloys, additive manufacturing, and the development and application of the nanoindentation technique. He published 260 papers in peer reviewed international journals and is an editor of Acta Materialia and Scripta Materialia. He is an elected Fellow of both the National Academies of Engineering and Sciences of India, and TWAS-The World Academy of Sciences, and is a recipient of the Scopus Young Scientist and National Metallurgist Day awards, Shanti Swarup Bhatnagar and TWAS prizes (both in Engineering Sciences category), and Swarnajayanthi and JC Bose National Fellowships. He delivered the CNR Rao Prize Lecture in Advanced Materials of the Materials Research Society of India and the Lee Hsun Award Lecture of IMR, Chinese Academy of Sciences. He is an Honorary Professor at the International Centre for Materials Science, Jawaharlal Nehru Centre for Advanced Scientific Research, India and Qiushi Distinguished Visiting Professor of Zhejiang University, China.