培训课主題：Spray-based Advanced Manufacturing

讲授人：Dr. Martin Jun  

𝕴Dr. Martin Jun is an Associate Professor of the School of Mechanical Engineering at Purdue University, West Lafayette, IN, USA. He received the BSc and MASc degrees in Mechanical Engineering from the University of British Columbia, Vancouver, Canada in 1998 and 2000, respectively. He then received his PhD degree in 2005 from the University of Illinois at Urbana-Champaign in the Department of Mechanical Science and Engineering. His main research focus is on advanced multi-scale and multi-material manufacturing processes and technologies for various applications such as sensing, optics, aerospace, biomedical, and energy. He has authored over 90 peer-reviewed journal publications. He is the recipient of the 2011 SME Outstanding Young Manufacturing Engineer Award, 2012 Canadian Society of Mechanical Engineers I.W. Smith Award for Outstanding Achievements, and 2015 Korean Society of Manufacturing Technology Engineers Damwoo Award.

☂  Although spray deposition is widely used in a number of different industries owing to its high throughput, versatility, and ease of use, precise control of spray deposition is difficult due to the stochastic nature of spray generation and variations in droplet diameters, velocities, and directions. Precise control of spray deposition would require precise control of impingement dynamics of each droplet in the spray, i.e., how each droplet behaves upon impact onto a substrate. In a typical spray nozzle, atomization and spray control are coupled together and nozzles are designed to perform atomization and spray shape control simultaneously. In this presentation, decoupling of atomization and spray control processes is introduced; atomization will be performed first and only small droplets will be carried to the nozzle so that droplet size variability can be reduced and spray control is easier at the nozzle, allowing decrease in the spray size. Focused spray and spray velocity control will be achieved by creating a pressure drop with relatively high speed gas at the center of the nozzle. Applications of the decoupled spray nozzle designed and built will be discussed in this talk. In this presentation, the use of cold spray for additive manufacturing will also be discussed. Cold spray is used a lot for welding or repair of expensive parts. How the cold spray can be used for additive manufacturing will be discussed as well.