S. Chandra, Centre for Advanced Coating Technology, University of Toronto, Toronto, ON, Canada; A. McDonald, M. Raessi, J. Mostaghimi, University of Toronto, Toronto, ON, Canada; C. Moreau, National Research Council Canada (CNRC-NRC), Boucherville,, QC, 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.
Summary: Plasma-sprayed molybdenum particles impacting glass surfaces held at 25 and 400C was photographed. An analytical model was developed to estimate the contact resistance between the splat and glass. The contact resistance was two orders of magnitude smaller on glass held at 400C. A numerical model was used 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
