Dr Saurav Goel, School of Mechanical and Aerospace Engineering,Queen’s University Belfast
Contact Loading Studies Using Molecular Dynamics Simulation: A Tested Bed for Ultra-precision Manufacturing
Miniaturization of products has become a timely need because one can drive multifarious benefits from such products, namely, savings in materials, space and power consumption. It increases system’s overall efficiency and gives ease of transportation but at the same time poses problems in handling and packaging. In spite of various challenges at multiple levels and at various scales, miniaturization is attracting global interest. Therefore, the demand for ultra-precision machined devices and components is growing at a rapid pace in various areas such as aerospace, energy, optical, electronics and bio-medical industries. While some ultra-precision products are becoming larger and larger (the size of a finished silicon wafer reached 300 mm in the year 2000), the sizes of many other precision components, such as fuel injectors and bearings, have been significantly reduced to meet the functional requirements and to reduce manufacturing and product costs. The need for tight dimensional tolerances and miniaturization for such products is driven by the global mission to reduce emissions and increase the efficiency of IC-engines. This is just one example of how environment and sustainability issues are increasingly driving ultra-precision technologies. Other examples can be found in optical devices and computer chips, where the required tolerances are approaching the atomic length scale. Driven by these requirements, ultra-precision manufacturing processes have emerged as a powerful tool for manipulating optical, electrical and mechanical properties of components by changing their surface and sub-surface structure at the nanometre length scale.
In fact, the most recent perspective on this has been that “Ultra precision engineering is doing for light what integrated circuits did for electronics”. Various ultra-precision material removal processes can be classified into mechanical, physical, or chemical processes depending on the nature of the mechanism of the material removal. While physical and chemical machining processes are restricted to specific materials and applications, machining by mechanical means is considered to be almost universal in its applicability to almost all the materials. However, one of the formidable challenges to analyze and improve the mechanical based ultra-precision machining processes is that the mode of material removal at fine precision level changes from continuous to discrete. An accurate understanding of this phenomena requires an insight into the energetic, structural, dynamic and rheological aspects of the system. Also, it has now been realized that it is not the atomic scale discreteness but the atomic scale machined surface roughness which causes the dramatic differences between the results obtained for nano-tribological problems using continuum mechanics principles and hence understanding the relevant atomic level phenomena is the key to obtaining full knowledge of the atomistic mechanism of ultra-precision machining and this can be accomplished efficiently through the use of atomic simulations which will be the main focus of this talk.
ABOUT THE PRESENTER
Dr Saurav Goel is a Lecturer and an early career investigator in the School of Mechanical and Aerospace Engineering at Queen’s University Belfast. He joined QUB in June 2013 after completing his PhD from Heriot-Watt University (HWU), UK. His PhD thesis titled “An atomistic investigation on the nanometric cutting mechanism of hard, brittle materials” resulted in 15 international journal papers and an award of Postgraduate Research Thesis Prize from the School of Engineering and Physical Sciences of HWU.
He has worked for a number of years on various materials to understand their high pressure response and in this process has achieved several benchmarks. In the first year of his PhD, he secured third prize in the poster competition at the 12th International Conference organized by the European Society of Precision Engineers and Nanotechnology (EUSPEN) at Stockholm, Sweden. Following this, he was selected to show his research at the SET for Britain Exhibition in the Engineering section held at the House of Commons in March 2013. Also, it was during this time that Heidenhain Gmbh awarded him a student scholarship to attend the 13th EUSPEN International Conference in Germany. Towards PhD completion, he secured the award of John Moyce Lessells Scholarship from the Royal Society of Edinburgh in 2013 which enabled him to work directly with the world leader in Precision Engineering at Keio University, Japan for three months to explore cutting mechanics of brittle materials like silicon and silicon carbide. This visit was highlighted in the newsletter of Scotland’s National Academy (Issue No. 42, Spring 2014 edition) and also resulted in four joint publications.
Over the years, he has expanded his research beyond traditional academic boundaries and is now supervising PhD students in other research areas such as, layer by layer assembly (LbL) processes for biomedical applications, thermal spraying processes, finite element simulation of hard turning processes and nanoindentation and nanoscratching studies and ultra-high precision diamond machining processes. He is among the first to publish results using long range potential functions and his contributions in the field of Si and SiC machining are considered novel. Recently, he has finished Post Graduate certification in higher education and teaching and Chartered Engineer from IMechE.
DATE: Friday, 13 May 2016
VENUE: MSG-025 MSSI Building Extension
TEA/COFFEE WILL BE AVAILABLE AT 14h45
For further information, please contact: email@example.com