| Fragmentation of Plasma-Sprayed Molybdenum Particles on Glass Surfaces | ||
| Dr. Sanjeev Chandra1, Mr. André McDonald1, Mr. Mehdi Raessi1, Dr. Christian Moreau2 and Dr. Javad Mostaghimi1, 1Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, ON M5S 3G8, Canada, 2Industrial Materials Institute, National Research Council Canada, 75 de Mortagne, Boucherville, QC J4B 6Y4, Canada The impact of plasma-sprayed molybdenum particles on glass surfaces held at 25 and 400oC was photographed. A two-color pyrometer was used to collect thermal radiation from the particles to follow their temperature evolution and to calculate the splat cooling rate. Significant fragmentation of the splat on the surface at 25oC was observed. An analytical model, which used the splat cooling rate, was developed to estimate the contact resistance between the splat and glass. The contact resistance was approximately two orders of magnitude smaller on the surface at 400oC, indicating faster solidification, which reduced splashing. Using a 3D model of droplet impact and solidification, numerical simulations were performed to support the assumptions made in developing the analytical model and to verify the values of contact resistance obtained from the analytical model. The splat morphology and disintegration pattern of the numerical results were in good agreement with the experimental data. | ||